diff --git a/b2g/app/b2g.js b/b2g/app/b2g.js
index 0080a4bf21d3..9e46b6dcc3eb 100644
--- a/b2g/app/b2g.js
+++ b/b2g/app/b2g.js
@@ -886,10 +886,6 @@ pref("network.sntp.timeout", 30); // In seconds.
 
 // Enable dataStore
 pref("dom.datastore.enabled", true);
-// When an entry is changed, use two timers to fire system messages in a more
-// moderate pattern.
-pref("dom.datastore.sysMsgOnChangeShortTimeoutSec", 10);
-pref("dom.datastore.sysMsgOnChangeLongTimeoutSec", 60);
 
 // DOM Inter-App Communication API.
 pref("dom.inter-app-communication-api.enabled", true);
diff --git a/dom/datastore/DataStoreChangeNotifier.jsm b/dom/datastore/DataStoreChangeNotifier.jsm
index bbf44a1f7ced..64951f3ca43c 100644
--- a/dom/datastore/DataStoreChangeNotifier.jsm
+++ b/dom/datastore/DataStoreChangeNotifier.jsm
@@ -23,33 +23,12 @@ XPCOMUtils.defineLazyServiceGetter(this, "dataStoreService",
                                    "@mozilla.org/datastore-service;1",
                                    "nsIDataStoreService");
 
-XPCOMUtils.defineLazyServiceGetter(this, "systemMessenger",
-                                   "@mozilla.org/system-message-internal;1",
-                                   "nsISystemMessagesInternal");
-
-var kSysMsgOnChangeShortTimeoutSec =
-    Services.prefs.getIntPref("dom.datastore.sysMsgOnChangeShortTimeoutSec");
-var kSysMsgOnChangeLongTimeoutSec =
-    Services.prefs.getIntPref("dom.datastore.sysMsgOnChangeLongTimeoutSec");
-
 this.DataStoreChangeNotifier = {
   children: [],
   messages: [ "DataStore:Changed", "DataStore:RegisterForMessages",
               "DataStore:UnregisterForMessages",
               "child-process-shutdown" ],
 
-  // These hashes are used for storing the mapping between the datastore
-  // identifiers (name | owner manifest URL) and their correspondent timers. 
-  // The object literal is defined as below:
-  //
-  // {
-  //   "datastore name 1|owner manifest URL 1": timer1,
-  //   "datastore name 2|owner manifest URL 2": timer2,
-  //   ...
-  // }
-  sysMsgOnChangeShortTimers: {},
-  sysMsgOnChangeLongTimers: {},
-
   init: function() {
     debug("init");
 
@@ -80,8 +59,7 @@ this.DataStoreChangeNotifier = {
   },
 
   broadcastMessage: function broadcastMessage(aData) {
-    debug("broadcast");
-
+    debug("Broadast");
     this.children.forEach(function(obj) {
       if (obj.store == aData.store && obj.owner == aData.owner) {
         obj.mm.sendAsyncMessage("DataStore:Changed:Return:OK", aData);
@@ -89,69 +67,6 @@ this.DataStoreChangeNotifier = {
     });
   },
 
-  broadcastSystemMessage: function(aStore, aOwner) {
-    debug("broadcastSystemMessage");
-
-    // Clear relevant timers.
-    var storeKey = aStore + "|" + aOwner;
-    var shortTimer = this.sysMsgOnChangeShortTimers[storeKey];
-    if (shortTimer) {
-      shortTimer.cancel();
-      delete this.sysMsgOnChangeShortTimers[storeKey];
-    }
-    var longTimer = this.sysMsgOnChangeLongTimers[storeKey];
-    if (longTimer) {
-      longTimer.cancel();
-      delete this.sysMsgOnChangeLongTimers[storeKey];
-    }
-
-    // Get all the manifest URLs of the apps which can access the datastore.
-    var manifestURLs = dataStoreService.getAppManifestURLsForDataStore(aStore);
-    var enumerate = manifestURLs.enumerate();
-    while (enumerate.hasMoreElements()) {
-      var manifestURL = enumerate.getNext().QueryInterface(Ci.nsISupportsString);
-      debug("Notify app " + manifestURL + " of datastore updates");
-      // Send the system message 'datastore-update-{store name}' to all the
-      // pages for these apps. With the manifest URL of the owner in the message
-      // payload, it notifies the consumer a sync operation should be performed.
-      systemMessenger.sendMessage("datastore-update-" + aStore,
-                                  { owner: aOwner },
-                                  null,
-                                  Services.io.newURI(manifestURL, null, null));
-    }
-  },
-
-  // Use the following logic to broadcast system messages in a moderate pattern.
-  // 1. When an entry is changed, start a short timer and a long timer.
-  // 2. If an entry is changed while the short timer is running, reset it.
-  //    Do not reset the long timer.
-  // 3. Once either fires, broadcast the system message and cancel both timers.
-  setSystemMessageTimeout: function(aStore, aOwner) {
-    debug("setSystemMessageTimeout");
-
-    var storeKey = aStore + "|" + aOwner;
-    
-    // Reset the short timer.
-    var shortTimer = this.sysMsgOnChangeShortTimers[storeKey];
-    if (!shortTimer) {
-      shortTimer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
-      this.sysMsgOnChangeShortTimers[storeKey] = shortTimer;
-    } else {
-      shortTimer.cancel();
-    }
-    shortTimer.initWithCallback({ notify: this.broadcastSystemMessage.bind(this, aStore, aOwner) },
-                                kSysMsgOnChangeShortTimeoutSec * 1000,
-                                Ci.nsITimer.TYPE_ONE_SHOT);
-
-    // Set the long timer if necessary.
-    if (!this.sysMsgOnChangeLongTimers[storeKey]) {
-      var longTimer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
-      this.sysMsgOnChangeLongTimers[storeKey] = longTimer;
-      longTimer.initWithCallback({ notify: this.broadcastSystemMessage.bind(this, aStore, aOwner) },
-                                 kSysMsgOnChangeLongTimeoutSec * 1000,
-                                 Ci.nsITimer.TYPE_ONE_SHOT);
-    }
-  },
 
   receiveMessage: function(aMessage) {
     debug("receiveMessage ");
@@ -174,7 +89,6 @@ this.DataStoreChangeNotifier = {
     switch (aMessage.name) {
       case "DataStore:Changed":
         this.broadcastMessage(aMessage.data);
-        this.setSystemMessageTimeout(aMessage.data.store, aMessage.data.owner);
         break;
 
       case "DataStore:RegisterForMessages":
diff --git a/dom/datastore/DataStoreService.cpp b/dom/datastore/DataStoreService.cpp
index 580246bc54be..a30a513a8d79 100644
--- a/dom/datastore/DataStoreService.cpp
+++ b/dom/datastore/DataStoreService.cpp
@@ -33,11 +33,9 @@
 #include "nsIDocument.h"
 #include "nsIDOMGlobalPropertyInitializer.h"
 #include "nsIIOService.h"
-#include "nsIMutableArray.h"
 #include "nsIObserverService.h"
 #include "nsIPermissionManager.h"
 #include "nsIScriptSecurityManager.h"
-#include "nsISupportsPrimitives.h"
 #include "nsIUUIDGenerator.h"
 #include "nsPIDOMWindow.h"
 #include "nsIURI.h"
@@ -377,24 +375,6 @@ GetDataStoreInfosEnumerator(const uint32_t& aAppId,
   return PL_DHASH_NEXT;
 }
 
-PLDHashOperator
-GetAppManifestURLsEnumerator(const uint32_t& aAppId,
-                             DataStoreInfo* aInfo,
-                             void* aUserData)
-{
-  AssertIsInMainProcess();
-  MOZ_ASSERT(NS_IsMainThread());
-
-  auto* manifestURLs = static_cast<nsIMutableArray*>(aUserData);
-  nsCOMPtr<nsISupportsString> manifestURL(do_CreateInstance(NS_SUPPORTS_STRING_CONTRACTID));
-  if (manifestURL) {
-    manifestURL->SetData(aInfo->mManifestURL);
-    manifestURLs->AppendElement(manifestURL, false);
-  }
-
-  return PL_DHASH_NEXT;
-}
-
 // This class is useful to enumerate the add permissions for each app.
 class MOZ_STACK_CLASS AddPermissionsData
 {
@@ -1077,31 +1057,6 @@ DataStoreService::GetDataStoreInfos(const nsAString& aName,
   return NS_OK;
 }
 
-NS_IMETHODIMP
-DataStoreService::GetAppManifestURLsForDataStore(const nsAString& aName,
-                                                 nsIArray** aManifestURLs)
-{
-  ASSERT_PARENT_PROCESS()
-  MOZ_ASSERT(NS_IsMainThread());
-
-  nsCOMPtr<nsIMutableArray> manifestURLs = do_CreateInstance(NS_ARRAY_CONTRACTID);
-  if (!manifestURLs) {
-    return NS_ERROR_OUT_OF_MEMORY;
-  }
-
-  HashApp* apps = nullptr;
-  if (mStores.Get(aName, &apps)) {
-    apps->EnumerateRead(GetAppManifestURLsEnumerator, manifestURLs.get());
-  }
-  if (mAccessStores.Get(aName, &apps)) {
-    apps->EnumerateRead(GetAppManifestURLsEnumerator, manifestURLs.get());
-  }
-
-  *aManifestURLs = manifestURLs;
-  NS_ADDREF(*aManifestURLs);
-  return NS_OK;
-}
-
 bool
 DataStoreService::CheckPermission(nsIPrincipal* aPrincipal)
 {
diff --git a/dom/datastore/nsIDataStoreService.idl b/dom/datastore/nsIDataStoreService.idl
index adb2b2f50ff7..b2b3d658630c 100644
--- a/dom/datastore/nsIDataStoreService.idl
+++ b/dom/datastore/nsIDataStoreService.idl
@@ -7,9 +7,8 @@
 
 interface nsIDOMWindow;
 interface nsIPrincipal;
-interface nsIArray;
 
-[scriptable, uuid(79944b1c-187d-11e4-abb6-74d02b97e723)]
+[scriptable, uuid(9b59c49a-0cd7-11e4-b096-74d02b97e723)]
 interface nsIDataStoreService : nsISupports
 {
   void installDataStore(in unsigned long appId,
@@ -28,7 +27,5 @@ interface nsIDataStoreService : nsISupports
                             in DOMString name,
                             in DOMString owner);
 
-  nsIArray getAppManifestURLsForDataStore(in DOMString name);
-
   boolean checkPermission(in nsIPrincipal principal);
 };
diff --git a/dom/datastore/tests/file_notify_system_message.html b/dom/datastore/tests/file_notify_system_message.html
deleted file mode 100644
index 05e9153cd07d..000000000000
--- a/dom/datastore/tests/file_notify_system_message.html
+++ /dev/null
@@ -1,122 +0,0 @@
-<!DOCTYPE HTML>
-<html>
-<head>
-  <meta charset="utf-8">
-  <title>Test for DataStore - notify updates with system messages</title>
-</head>
-<body>
-<p id="display"></p>
-<div id="content" style="display: none">
-
-</div>
-<pre id="test">
-  <script type="application/javascript;version=1.7">
-
-  var gStore;
-  var gChangeId = null;
-  var gChangeOperation = null;
-  var gIsSystemMessageFired = false;
-
-  function is(a, b, msg) {
-    alert((a === b ? 'OK' : 'KO') + ' ' + msg)
-  }
-
-  function ok(a, msg) {
-    alert((a ? 'OK' : 'KO')+ ' ' + msg)
-  }
-
-  function cbError() {
-    alert('KO error');
-  }
-
-  function finish() {
-    alert('DONE');
-  }
-
-  function testGetDataStores() {
-    navigator.getDataStores('foo').then(function(stores) {
-      is(stores.length, 1, "getDataStores('foo') returns 1 element");
-      is(stores[0].name, 'foo', 'The dataStore.name is foo');
-      is(stores[0].readOnly, false, 'The dataStore foo is not in readonly');
-
-      gStore = stores[0];
-      runTest();
-    }, cbError);
-  }
-
-  function testStoreAdd(value, expectedId) {
-    gStore.add(value).then(function(id) {
-      is(id, expectedId, "store.add() is called");
-    }, cbError);
-  }
-
-  function eventListener(evt) {
-    ok(evt instanceof DataStoreChangeEvent, "DataStoreChangeEvent has been received");
-    ok(evt, "OnChangeListener is called with data");
-    is(/[0-9a-zA-Z]{8}-[0-9a-zA-Z]{4}-[0-9a-zA-Z]{4}-[0-9a-zA-Z]{4}-[0-9a-zA-Z]{12}/.test(evt.revisionId), true, "event.revisionId returns something");
-    is(evt.id, gChangeId, "OnChangeListener is called with the right ID: " + evt.id);
-    is(evt.operation, gChangeOperation, "OnChangeListener is called with the right operation:" + evt.operation + " " + gChangeOperation);
-    runTest();
-  }
-
-  function onDatastoreUpdateFoo(message) {
-    gIsSystemMessageFired = true;
-    ok(true, "System message 'datastore-update-foo' has been received");
-    runTest();
-  }
-
-  var tests = [
-    // Test for GetDataStore.
-    testGetDataStores,
-
-    // Add onchange = function.
-    function() {
-      gStore.onchange = eventListener;
-      is(gStore.onchange, eventListener, "onChange is set");
-      runTest();
-    },
-
-    // Set system message handler.
-    function() {
-      navigator.mozSetMessageHandler('datastore-update-foo', onDatastoreUpdateFoo);
-      runTest();
-    },
-
-    // Add.
-    function() { gChangeId = 1; gChangeOperation = 'added';
-                 testStoreAdd({ number: 42 }, 1); },
-
-    // Remove event listener.
-    function() {
-      gStore.removeEventListener('change', eventListener);
-      runTest();
-    },
-
-    // Wait enough amount of time for the system message to fire.
-    function() {
-      setTimeout(runTest, 10000);
-    },
-
-    // Ensure the system message has fired and no more pending ones.
-    function() {
-      ok(!navigator.mozHasPendingMessage('datastore-update-foo'), "No more pending system message");
-      ok(gIsSystemMessageFired, "The system message has fired");
-      runTest();
-    }
-  ];
-
-  function runTest() {
-    if (!tests.length) {
-      finish();
-      return;
-    }
-
-    var test = tests.shift();
-    test();
-  }
-
-  runTest();
-  </script>
-</pre>
-</body>
-</html>
diff --git a/dom/datastore/tests/mochitest.ini b/dom/datastore/tests/mochitest.ini
index e1ca2818206b..fd3972597dbe 100644
--- a/dom/datastore/tests/mochitest.ini
+++ b/dom/datastore/tests/mochitest.ini
@@ -30,7 +30,6 @@ support-files =
   file_sync_common.js
   file_bug1008044.html
   file_bug957086.html
-  file_notify_system_message.html
 
 [test_app_install.html]
 [test_readonly.html]
@@ -51,5 +50,3 @@ support-files =
 [test_transactions.html]
 [test_bug1008044.html]
 [test_bug957086.html]
-[test_notify_system_message.html]
-skip-if = toolkit == 'gonk' # b2g
diff --git a/dom/datastore/tests/test_app_install.html b/dom/datastore/tests/test_app_install.html
index 8c326d337048..c03f249326d0 100644
--- a/dom/datastore/tests/test_app_install.html
+++ b/dom/datastore/tests/test_app_install.html
@@ -10,6 +10,10 @@
 <div id="container"></div>
   <script type="application/javascript;version=1.7">
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
 
   var gBaseURL = 'http://test/tests/dom/datastore/tests/';
@@ -22,14 +26,8 @@
      { "type": "webapps-manage", "allow": 1, "context": document }],
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, function() {
-
-        if (SpecialPowers.isMainProcess()) {
-          SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-        }
         gGenerator.next(); });
     });
 
diff --git a/dom/datastore/tests/test_arrays.html b/dom/datastore/tests/test_arrays.html
index 513a6de28f6a..a1d81a2f48b4 100644
--- a/dom/datastore/tests/test_arrays.html
+++ b/dom/datastore/tests/test_arrays.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_basic.html b/dom/datastore/tests/test_basic.html
index c774b146c9f9..25d6637ef505 100644
--- a/dom/datastore/tests/test_basic.html
+++ b/dom/datastore/tests/test_basic.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_basic_worker.html b/dom/datastore/tests/test_basic_worker.html
index 70fadecd8fa1..be940e8771b1 100644
--- a/dom/datastore/tests/test_basic_worker.html
+++ b/dom/datastore/tests/test_basic_worker.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_bug1008044.html b/dom/datastore/tests/test_bug1008044.html
index c22131f2379c..97164c396cad 100644
--- a/dom/datastore/tests/test_bug1008044.html
+++ b/dom/datastore/tests/test_bug1008044.html
@@ -77,18 +77,12 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.ipc.browser_frames.oop_by_default", true],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -123,6 +117,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_bug924104.html b/dom/datastore/tests/test_bug924104.html
index 3896a108b302..5b22acf11dbd 100644
--- a/dom/datastore/tests/test_bug924104.html
+++ b/dom/datastore/tests/test_bug924104.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_bug957086.html b/dom/datastore/tests/test_bug957086.html
index ac8f31ee09b1..1abb1f4c1538 100644
--- a/dom/datastore/tests/test_bug957086.html
+++ b/dom/datastore/tests/test_bug957086.html
@@ -81,18 +81,12 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.ipc.browser_frames.oop_by_default", true],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -130,6 +124,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_bug976311.html b/dom/datastore/tests/test_bug976311.html
index 35f9aba480a5..4922dd2db350 100644
--- a/dom/datastore/tests/test_bug976311.html
+++ b/dom/datastore/tests/test_bug976311.html
@@ -82,17 +82,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -130,6 +124,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_bug986056.html b/dom/datastore/tests/test_bug986056.html
index 3d14cb666c5d..2376f71483ce 100644
--- a/dom/datastore/tests/test_bug986056.html
+++ b/dom/datastore/tests/test_bug986056.html
@@ -75,17 +75,12 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
+    // Enabling mozBrowser
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.pushPrefEnv({"set": [["dom.mozBrowserFramesEnabled", true]]}, runTest);
     },
@@ -139,6 +134,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_certifiedApp.html b/dom/datastore/tests/test_certifiedApp.html
index e4a328c2d0d9..0b78ccbc8146 100644
--- a/dom/datastore/tests/test_certifiedApp.html
+++ b/dom/datastore/tests/test_certifiedApp.html
@@ -77,8 +77,6 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", false]]}, runTest);
     },
@@ -91,10 +89,6 @@
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -129,6 +123,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_changes.html b/dom/datastore/tests/test_changes.html
index c2a67b1addd2..434c4c0f4c7f 100644
--- a/dom/datastore/tests/test_changes.html
+++ b/dom/datastore/tests/test_changes.html
@@ -121,17 +121,12 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
+    // Enabling mozBrowser
     function() {
-   	  if (SpecialPowers.isMainProcess()) {
-   	    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-   	  }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.pushPrefEnv({"set": [["dom.mozBrowserFramesEnabled", true]]}, runTest);
     },
@@ -174,6 +169,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_duplicate.html b/dom/datastore/tests/test_duplicate.html
index 8589d4408261..e9ecca2ab9a4 100644
--- a/dom/datastore/tests/test_duplicate.html
+++ b/dom/datastore/tests/test_duplicate.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_keys.html b/dom/datastore/tests/test_keys.html
index 9bc2ac2b88b8..dced0354ef3b 100644
--- a/dom/datastore/tests/test_keys.html
+++ b/dom/datastore/tests/test_keys.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_notify_system_message.html b/dom/datastore/tests/test_notify_system_message.html
deleted file mode 100644
index dc32f79f5a5f..000000000000
--- a/dom/datastore/tests/test_notify_system_message.html
+++ /dev/null
@@ -1,138 +0,0 @@
-<!DOCTYPE HTML>
-<html>
-<head>
-  <meta charset="utf-8">
-  <title>Test for DataStore - notify updates with system messages</title>
-  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
-</head>
-<body>
-<div id="container"></div>
-  <script type="application/javascript;version=1.7">
-
-  var gHostedManifestURL = 'http://test/tests/dom/datastore/tests/file_app.sjs?testToken=file_notify_system_message.html';
-  var gHostedPageURL = 'http://mochi.test:8888/tests/dom/datastore/tests/file_notify_system_message.html';
-  var gApp;
-
-  function cbError() {
-    ok(false, "Error callback invoked");
-    finish();
-  }
-
-  function installApp() {
-    var request = navigator.mozApps.install(gHostedManifestURL);
-    request.onerror = cbError;
-    request.onsuccess = function() {
-      gApp = request.result;
-      runTest();
-    }
-  }
-
-  function uninstallApp() {
-    // Uninstall the app.
-    var request = navigator.mozApps.mgmt.uninstall(gApp);
-    request.onerror = cbError;
-    request.onsuccess = function() {
-      // All done.
-      info("All done");
-      runTest();
-    }
-  }
-
-  function testApp() {
-    var ifr = document.createElement('iframe');
-    ifr.setAttribute('mozbrowser', 'true');
-    ifr.setAttribute('mozapp', gApp.manifestURL);
-    ifr.setAttribute('src', gApp.manifest.launch_path);
-    var domParent = document.getElementById('container');
-
-    // Set us up to listen for messages from the app.
-    var listener = function(e) {
-      var message = e.detail.message;
-      if (/^OK/.exec(message)) {
-        ok(true, "Message from app: " + message);
-      } else if (/KO/.exec(message)) {
-        ok(false, "Message from app: " + message);
-      } else if (/DONE/.exec(message)) {
-        ok(true, "Messaging from app complete");
-        ifr.removeEventListener('mozbrowsershowmodalprompt', listener);
-        domParent.removeChild(ifr);
-        runTest();
-      }
-    }
-
-    // This event is triggered when the app calls "alert".
-    ifr.addEventListener('mozbrowsershowmodalprompt', listener, false);
-    domParent.appendChild(ifr);
-  }
-
-  var tests = [
-    // Permissions.
-    function() {
-      SpecialPowers.pushPermissions(
-        [{ "type": "browser", "allow": 1, "context": document },
-         { "type": "embed-apps", "allow": 1, "context": document },
-         { "type": "webapps-manage", "allow": 1, "context": document }], runTest);
-    },
-
-    // Preferences.
-    function() {
-      SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
-                                         ["dom.sysmsg.enabled", true],
-                                         ["dom.testing.ignore_ipc_principal", true],
-                                         ["dom.testing.datastore_enabled_for_hosted_apps", true],
-                                         ["dom.mozBrowserFramesEnabled", true]]}, runTest);
-    },
-
-    function() {
-      SpecialPowers.setAllAppsLaunchable(true);
-      // No confirmation needed when an app is installed.
-      SpecialPowers.autoConfirmAppInstall(runTest);
-    },
-
-    function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-        SpecialPowers.Cu.import("resource://gre/modules/Services.jsm");
-        var ioService = SpecialPowers.Cc["@mozilla.org/network/io-service;1"]
-                                     .getService(SpecialPowers.Ci.nsIIOService);
-        var systemMessenger = SpecialPowers.Cc["@mozilla.org/system-message-internal;1"]
-                              .getService(SpecialPowers.Ci.nsISystemMessagesInternal);
-        systemMessenger.registerPage("datastore-update-foo",
-                                     ioService.newURI(gHostedPageURL, null, null),
-                                     ioService.newURI(gHostedManifestURL, null, null));
-      }
-      runTest();
-    },
-
-    // Installing the app.
-    installApp,
-
-    // Run tests in app.
-    testApp,
-
-    // Uninstall the app.
-    uninstallApp
-  ];
-
-  function runTest() {
-    if (!tests.length) {
-      finish();
-      return;
-    }
-
-    var test = tests.shift();
-    test();
-  }
-
-  function finish() {
-    SimpleTest.finish();
-  }
-
-  SimpleTest.waitForExplicitFinish();
-  runTest();
-  </script>
-</body>
-</html>
diff --git a/dom/datastore/tests/test_oop.html b/dom/datastore/tests/test_oop.html
index e275b2d1b3d1..989904341e67 100644
--- a/dom/datastore/tests/test_oop.html
+++ b/dom/datastore/tests/test_oop.html
@@ -77,18 +77,12 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.ipc.browser_frames.oop_by_default", true],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -123,6 +117,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_oop_events.html b/dom/datastore/tests/test_oop_events.html
index c57f93de6572..d97d674c8a91 100644
--- a/dom/datastore/tests/test_oop_events.html
+++ b/dom/datastore/tests/test_oop_events.html
@@ -105,18 +105,12 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.ipc.browser_frames.oop_by_default", true],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -153,6 +147,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_readonly.html b/dom/datastore/tests/test_readonly.html
index 52541cd26186..559b8d0f3eb6 100644
--- a/dom/datastore/tests/test_readonly.html
+++ b/dom/datastore/tests/test_readonly.html
@@ -30,10 +30,6 @@
   }
 
   function runTest() {
-    if (SpecialPowers.isMainProcess()) {
-      SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-    }
-
     SpecialPowers.setAllAppsLaunchable(true);
     SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
 
@@ -99,10 +95,12 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                     ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                     ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                      ["dom.testing.ignore_ipc_principal", true],
                                      ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
   </script>
diff --git a/dom/datastore/tests/test_sync.html b/dom/datastore/tests/test_sync.html
index 15ab46c910c5..b45472c88ba2 100644
--- a/dom/datastore/tests/test_sync.html
+++ b/dom/datastore/tests/test_sync.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
     },
@@ -121,6 +115,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_sync_worker.html b/dom/datastore/tests/test_sync_worker.html
index 4e1d5d0507f3..904edea96e8f 100644
--- a/dom/datastore/tests/test_sync_worker.html
+++ b/dom/datastore/tests/test_sync_worker.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
     },
@@ -121,6 +115,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/datastore/tests/test_transactions.html b/dom/datastore/tests/test_transactions.html
index 26d974aa1cb1..7607b11fa5c3 100644
--- a/dom/datastore/tests/test_transactions.html
+++ b/dom/datastore/tests/test_transactions.html
@@ -77,17 +77,11 @@
     // Preferences
     function() {
       SpecialPowers.pushPrefEnv({"set": [["dom.datastore.enabled", true],
-                                         ["dom.datastore.sysMsgOnChangeShortTimeoutSec", 1],
-                                         ["dom.datastore.sysMsgOnChangeLongTimeoutSec", 3],
                                          ["dom.testing.ignore_ipc_principal", true],
                                          ["dom.testing.datastore_enabled_for_hosted_apps", true]]}, runTest);
     },
 
     function() {
-      if (SpecialPowers.isMainProcess()) {
-        SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
-      }
-
       SpecialPowers.setAllAppsLaunchable(true);
       SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
       runTest();
@@ -122,6 +116,10 @@
     SimpleTest.finish();
   }
 
+  if (SpecialPowers.isMainProcess()) {
+    SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  }
+
   SimpleTest.waitForExplicitFinish();
   runTest();
   </script>
diff --git a/dom/messages/SystemMessageInternal.js b/dom/messages/SystemMessageInternal.js
index 74e24e38129d..727086896264 100644
--- a/dom/messages/SystemMessageInternal.js
+++ b/dom/messages/SystemMessageInternal.js
@@ -192,48 +192,31 @@ SystemMessageInternal.prototype = {
     // clean it up from the pending message queue when apps receive it.
     let messageID = gUUIDGenerator.generateUUID().toString();
 
-    let manifestURL = aManifestURI.spec;
-    let pageURLs = [];
-    if (aPageURI) {
-      pageURLs.push(aPageURI.spec);
-    } else {
-      // Send this message to all the registered pages of the app if |aPageURI|
-      // is not specified.
-      for (let i = 0; i < this._pages.length; i++) {
-        let page = this._pages[i];
-        if (page.type === aType && page.manifestURL === manifestURL) {
-          pageURLs.push(page.pageURL);
-        }
-      }
+    debug("Sending " + aType + " " + JSON.stringify(aMessage) +
+      " for " + aPageURI.spec + " @ " + aManifestURI.spec +
+      '; extra: ' + JSON.stringify(aExtra));
+
+    let result = this._sendMessageCommon(aType,
+                                         aMessage,
+                                         messageID,
+                                         aPageURI.spec,
+                                         aManifestURI.spec,
+                                         aExtra);
+    debug("Returned status of sending message: " + result);
+
+    // Don't need to open the pages and queue the system message
+    // which was not allowed to be sent.
+    if (result === MSG_SENT_FAILURE_PERM_DENIED) {
+      return;
     }
 
-    pageURLs.forEach(function(aPageURL) {
-      debug("Sending " + aType + " " + JSON.stringify(aMessage) +
-        " for " + aPageURL + " @ " + manifestURL +
-        '; extra: ' + JSON.stringify(aExtra));
+    let page = this._findPage(aType, aPageURI.spec, aManifestURI.spec);
+    if (page) {
+      // Queue this message in the corresponding pages.
+      this._queueMessage(page, aMessage, messageID);
 
-      let result = this._sendMessageCommon(aType,
-                                           aMessage,
-                                           messageID,
-                                           aPageURL,
-                                           manifestURL,
-                                           aExtra);
-      debug("Returned status of sending message: " + result);
-
-      // Don't need to open the pages and queue the system message
-      // which was not allowed to be sent.
-      if (result === MSG_SENT_FAILURE_PERM_DENIED) {
-        return;
-      }
-
-      let page = this._findPage(aType, aPageURL, manifestURL);
-      if (page) {
-        // Queue this message in the corresponding pages.
-        this._queueMessage(page, aMessage, messageID);
-
-        this._openAppPage(page, aMessage, aExtra, result);
-      }
-    }, this);
+      this._openAppPage(page, aMessage, aExtra, result);
+    }
   },
 
   broadcastMessage: function(aType, aMessage, aExtra) {
diff --git a/dom/messages/SystemMessagePermissionsChecker.jsm b/dom/messages/SystemMessagePermissionsChecker.jsm
index 89bcf6757349..433c87598754 100644
--- a/dom/messages/SystemMessagePermissionsChecker.jsm
+++ b/dom/messages/SystemMessagePermissionsChecker.jsm
@@ -15,8 +15,7 @@ Cu.import("resource://gre/modules/PermissionsTable.jsm");
 Cu.import("resource://gre/modules/PermissionSettings.jsm");
 
 this.EXPORTED_SYMBOLS = ["SystemMessagePermissionsChecker",
-                         "SystemMessagePermissionsTable",
-                         "SystemMessagePrefixPermissionsTable"];
+                         "SystemMessagePermissionsTable"];
 
 function debug(aStr) {
   // dump("SystemMessagePermissionsChecker.jsm: " + aStr + "\n");
@@ -123,18 +122,6 @@ this.SystemMessagePermissionsTable = {
   }
 };
 
-// This table maps system message prefix to permission(s), indicating only
-// the system messages with specified prefixes granted by the page's permissions
-// are allowed to be registered or sent to that page. Note the empty permission
-// set means this type of system message is always permitted.
-//
-// Note that this table is only used when the permission checker can't find a
-// match in SystemMessagePermissionsTable listed above.
-
-this.SystemMessagePrefixPermissionsTable = {
-  "datastore-update-": { },
-};
-
 this.SystemMessagePermissionsChecker = {
   /**
    * Return all the needed permission names for the given system message.
@@ -153,26 +140,16 @@ this.SystemMessagePermissionsChecker = {
 
     let permNames = SystemMessagePermissionsTable[aSysMsgName];
     if (permNames === undefined) {
-      // Try to look up in the prefix table.
-      for (let sysMsgPrefix in SystemMessagePrefixPermissionsTable) {
-        if (aSysMsgName.indexOf(sysMsgPrefix) === 0) {
-          permNames = SystemMessagePrefixPermissionsTable[sysMsgPrefix];
-          break;
-        }
-      }
-
-      if (permNames === undefined) {
-        debug("'" + aSysMsgName + "' is not associated with permissions. " +
-              "Please add them to the SystemMessage[Prefix]PermissionsTable.");
-        return null;
-      }
+      debug("'" + aSysMsgName + "' is not associated with permissions. " +
+            "Please add them to the SystemMessagePermissionsTable.");
+      return null;
     }
 
     let object = { };
     for (let permName in permNames) {
       if (PermissionsTable[permName] === undefined) {
         debug("'" + permName + "' for '" + aSysMsgName + "' is invalid. " +
-              "Please correct it in the SystemMessage[Prefix]PermissionsTable.");
+              "Please correct it in the SystemMessagePermissionsTable.");
         return null;
       }
 
@@ -180,7 +157,7 @@ this.SystemMessagePermissionsChecker = {
       let access = permNames[permName];
       if (!access || !Array.isArray(access)) {
         debug("'" + permName + "' is not associated with access array. " +
-              "Please correct it in the SystemMessage[Prefix]PermissionsTable.");
+              "Please correct it in the SystemMessagePermissionsTable.");
         return null;
       }
       object[permName] = appendAccessToPermName(permName, access);
diff --git a/dom/messages/interfaces/nsISystemMessagesInternal.idl b/dom/messages/interfaces/nsISystemMessagesInternal.idl
index 450206b2ba55..8df78278f076 100644
--- a/dom/messages/interfaces/nsISystemMessagesInternal.idl
+++ b/dom/messages/interfaces/nsISystemMessagesInternal.idl
@@ -13,12 +13,10 @@ interface nsIDOMWindow;
 interface nsISystemMessagesInternal : nsISupports
 {
   /*
-   * Allow any internal user to send a message of a given type to a given page
-   * of an app. The message will be sent to all the registered pages of the app
-   * when |pageURI| is not specified.
+   * Allow any internal user to broadcast a message of a given type.
    * @param type        The type of the message to be sent.
    * @param message     The message payload.
-   * @param pageURI     The URI of the page that will be opened. Nullable.
+   * @param pageURI     The URI of the page that will be opened.
    * @param manifestURI The webapp's manifest URI.
    * @param extra       Extra opaque information that will be passed around in the observer
    *                    notification to open the page.