Bug 1363421 - Part 2, delay the initialization of UserAgentOverrides.jsm until first nsHttpChannel is created. r=mcmanus

UAOverridesBootstrapper.js is introduced to delay the initialization of
UserAgentOverrides.jsm until the creation of the first nsHttpChannel.
Uninit will be triggered at profile-change-net-teardown because no network
traffice after this point.


MozReview-Commit-ID: F8Lpn6RyZEm

--HG--
extra : rebase_source : 7c3649b50ad8594dc0968961fbbd2766d0d98b0a

browser/components/nsBrowserGlue.js

@@ -37,7 +37,7 @@ XPCOMUtils.defineLazyGetter(this, "WeaveService", () =>
           RemotePrompt:false, SessionStore:false,
           ShellService:false, SimpleServiceDiscovery:false, TabCrashHandler:false,
           Task:false, UITour:false, WebChannel:false,
-          WindowsRegistry:false, webrtcUI:false, UserAgentOverrides: false */
+          WindowsRegistry:false, webrtcUI:false */
 
 /**
  * IF YOU ADD OR REMOVE FROM THIS LIST, PLEASE UPDATE THE LIST ABOVE AS WELL.
@@ -92,7 +92,6 @@ let initializedModules = {};
   ["WebChannel", "resource://gre/modules/WebChannel.jsm"],
   ["WindowsRegistry", "resource://gre/modules/WindowsRegistry.jsm"],
   ["webrtcUI", "resource:///modules/webrtcUI.jsm", "init"],
-  ["UserAgentOverrides", "resource://gre/modules/UserAgentOverrides.jsm"],
 ].forEach(([name, resource, init]) => {
   if (init) {
     XPCOMUtils.defineLazyGetter(this, name, () => {
@@ -516,8 +515,6 @@ BrowserGlue.prototype = {
       // and e10s are active together.
       E10SAccessibilityCheck.init();
     }
-
-    UserAgentOverrides.init();
   },
 
   // cleanup (called on application shutdown)
@@ -561,8 +558,6 @@ BrowserGlue.prototype = {
     os.removeObserver(this, "browser-search-engine-modified");
     os.removeObserver(this, "flash-plugin-hang");
     os.removeObserver(this, "xpi-signature-changed");
-
-    UserAgentOverrides.uninit();
   },
 
   _onAppDefaults: function BG__onAppDefaults() {

browser/installer/package-manifest.in

@@ -361,6 +361,8 @@
 @RESPATH@/components/BrowserElementParent.js
 @RESPATH@/components/FeedProcessor.manifest
 @RESPATH@/components/FeedProcessor.js
+@RESPATH@/components/UAOverridesBootstrapper.js
+@RESPATH@/components/UAOverridesBootstrapper.manifest
 @RESPATH@/components/WellKnownOpportunisticUtils.js
 @RESPATH@/components/WellKnownOpportunisticUtils.manifest
 #ifndef XP_MACOSX

mobile/android/chrome/content/browser.js

@@ -458,7 +458,6 @@ var BrowserApp = {
     CharacterEncoding.init();
     ActivityObserver.init();
     RemoteDebugger.init();
-    UserAgentOverrides.init();
     DesktopUserAgent.init();
     Distribution.init();
     Tabs.init();

mobile/android/installer/package-manifest.in

@@ -277,6 +277,8 @@
 @BINPATH@/components/BrowserElementParent.js
 @BINPATH@/components/FeedProcessor.manifest
 @BINPATH@/components/FeedProcessor.js
+@BINPATH@/components/UAOverridesBootstrapper.js
+@BINPATH@/components/UAOverridesBootstrapper.manifest
 @BINPATH@/components/WellKnownOpportunisticUtils.js
 @BINPATH@/components/WellKnownOpportunisticUtils.manifest
 @BINPATH@/components/mozProtocolHandler.js

netwerk/protocol/http/UAOverridesBootstrapper.js

@@ -0,0 +1,36 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const Ci = Components.interfaces;
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/UserAgentOverrides.jsm");
+
+function UAOverridesBootstrapper() {
+  this.init();
+}
+
+UAOverridesBootstrapper.prototype = {
+  init: function uaob_init() {
+    Services.obs.addObserver(this, "profile-change-net-teardown", false);
+    UserAgentOverrides.init();
+  },
+
+  observe: function uaob_observe(aSubject, aTopic, aData) {
+    if (aTopic == "profile-change-net-teardown") {
+      Services.obs.removeObserver(this, "profile-change-net-teardown");
+      UserAgentOverrides.uninit();
+    }
+  },
+
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver]),
+  classID: Components.ID("{965b0ca8-155b-11e7-93ae-92361f002671}")
+};
+
+const components = [UAOverridesBootstrapper];
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory(components);

netwerk/protocol/http/UAOverridesBootstrapper.manifest

@@ -0,0 +1,3 @@
+# UAOverridesBootstrapper.js
+component {965b0ca8-155b-11e7-93ae-92361f002671} UAOverridesBootstrapper.js process=main
+contract @mozilla.org/network/ua-overrides-bootstrapper;1 {965b0ca8-155b-11e7-93ae-92361f002671} process=main

netwerk/protocol/http/UserAgentOverrides.jsm

@@ -49,18 +49,24 @@ this.UserAgentOverrides = {
       // The http-on-useragent-request notification is disallowed in content processes.
     }
 
-    UserAgentUpdates.init(function(overrides) {
-      gOverrideForHostCache.clear();
-      if (overrides) {
-        for (let domain in overrides) {
-          overrides[domain] = getUserAgentFromOverride(overrides[domain]);
+    try {
+      UserAgentUpdates.init(function(overrides) {
+        gOverrideForHostCache.clear();
+        if (overrides) {
+          for (let domain in overrides) {
+            overrides[domain] = getUserAgentFromOverride(overrides[domain]);
+          }
+          overrides.get = function(key) { return this[key]; };
         }
-        overrides.get = function(key) { return this[key]; };
-      }
-      gUpdatedOverrides = overrides;
-    });
+        gUpdatedOverrides = overrides;
+      });
+
+      buildOverrides();
+    } catch (e) {
+      // UserAgentOverrides is initialized before profile is ready.
+      // UA override might not work correctly.
+    }
 
-    buildOverrides();
     gInitialized = true;
   },
 

netwerk/protocol/http/moz.build

@@ -119,6 +119,8 @@ LOCAL_INCLUDES += [
 ]
 
 EXTRA_COMPONENTS += [
+    'UAOverridesBootstrapper.js',
+    'UAOverridesBootstrapper.manifest',
     'WellKnownOpportunisticUtils.js',
     'WellKnownOpportunisticUtils.manifest',
 ]

netwerk/protocol/http/nsHttpHandler.cpp

@@ -333,6 +333,19 @@ nsHttpHandler::SetFastOpenOSSupport()
          mFastOpenSupported ? "" : "not"));
 }
 
+void
+nsHttpHandler::EnsureUAOverridesInit()
+{
+    MOZ_ASSERT(XRE_IsParentProcess());
+    MOZ_ASSERT(NS_IsMainThread());
+
+    nsresult rv;
+    nsCOMPtr<nsISupports> bootstrapper
+        = do_GetService("@mozilla.org/network/ua-overrides-bootstrapper;1", &rv);
+    MOZ_ASSERT(bootstrapper);
+    MOZ_ASSERT(NS_SUCCEEDED(rv));
+}
+
 nsHttpHandler::~nsHttpHandler()
 {
     LOG(("Deleting nsHttpHandler [this=%p]\n", this));
@@ -2103,6 +2116,11 @@ nsHttpHandler::NewProxiedChannel2(nsIURI *uri,
         net_EnsurePSMInit();
     }
 
+    if (XRE_IsParentProcess()) {
+        // Load UserAgentOverrides.jsm before any HTTP request is issued.
+        EnsureUAOverridesInit();
+    }
+
     uint64_t channelId;
     rv = NewChannelId(channelId);
     NS_ENSURE_SUCCESS(rv, rv);

netwerk/protocol/http/nsHttpHandler.h

@@ -403,6 +403,8 @@ private:
     void     NotifyObservers(nsIHttpChannel *chan, const char *event);
 
     void SetFastOpenOSSupport();
+
+    void EnsureUAOverridesInit();
 private:
 
     // cached services