diff --git a/toolkit/components/downloads/test/unit/test_download_samename.js b/toolkit/components/downloads/test/unit/test_download_samename.js
index c76c9153c9f0..c609e22447a9 100644
--- a/toolkit/components/downloads/test/unit/test_download_samename.js
+++ b/toolkit/components/downloads/test/unit/test_download_samename.js
@@ -57,21 +57,20 @@ let DownloadListener = {
         do_check_neq(file.leafName, prevFile.leafName);
       }
       this.prevFiles.push(file);
-    
+
       // get the contents of the file
       let fis = Cc["@mozilla.org/network/file-input-stream;1"].createInstance(Ci.nsIFileInputStream);
       fis.init(file, -1, -1, 0);
       var cstream = Cc["@mozilla.org/intl/converter-input-stream;1"].createInstance(Ci.nsIConverterInputStream);
       cstream.init(fis, "UTF-8", 0, 0);
-    
+
       let val = "";
-      let (str = {}) {  
-        let read = 0;
-        do {
-          read = cstream.readString(0xffffffff, str);
-          val += str.value;  
-        } while (read != 0);  
-      }
+      let str = {};
+      let read = 0;
+      do {
+        read = cstream.readString(0xffffffff, str);
+        val += str.value;
+      } while (read != 0);
       cstream.close();
 
       // check if the file contents match the expected ones
diff --git a/toolkit/components/places/tests/autocomplete/head_autocomplete.js b/toolkit/components/places/tests/autocomplete/head_autocomplete.js
index 9510086df4ea..70d03a886dad 100644
--- a/toolkit/components/places/tests/autocomplete/head_autocomplete.js
+++ b/toolkit/components/places/tests/autocomplete/head_autocomplete.js
@@ -10,7 +10,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/bookmarks/head_bookmarks.js b/toolkit/components/places/tests/bookmarks/head_bookmarks.js
index 67582d03b508..2ae00c14aa1e 100644
--- a/toolkit/components/places/tests/bookmarks/head_bookmarks.js
+++ b/toolkit/components/places/tests/bookmarks/head_bookmarks.js
@@ -11,7 +11,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/expiration/head_expiration.js b/toolkit/components/places/tests/expiration/head_expiration.js
index bbcd5dd5e021..f7f262e70fde 100644
--- a/toolkit/components/places/tests/expiration/head_expiration.js
+++ b/toolkit/components/places/tests/expiration/head_expiration.js
@@ -12,7 +12,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/favicons/head_favicons.js b/toolkit/components/places/tests/favicons/head_favicons.js
index b3a911239243..0b973e9ce018 100644
--- a/toolkit/components/places/tests/favicons/head_favicons.js
+++ b/toolkit/components/places/tests/favicons/head_favicons.js
@@ -11,7 +11,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/favicons/test_moz-anno_favicon_mime_type.js b/toolkit/components/places/tests/favicons/test_moz-anno_favicon_mime_type.js
index 334fd7ebb4e1..26e20f1329ed 100644
--- a/toolkit/components/places/tests/favicons/test_moz-anno_favicon_mime_type.js
+++ b/toolkit/components/places/tests/favicons/test_moz-anno_favicon_mime_type.js
@@ -58,46 +58,43 @@ function run_test()
             getService(Ci.nsIIOService);
 
   // Test that the default icon has the content type of image/png.
-  let (channel = ios.newChannelFromURI2(fs.defaultFavicon,
+  let channel = ios.newChannelFromURI2(fs.defaultFavicon,
                                         null,      // aLoadingNode
                                         Services.scriptSecurityManager.getSystemPrincipal(),
                                         null,      // aTriggeringPrincipal
                                         Ci.nsILoadInfo.SEC_NORMAL,
-                                        Ci.nsIContentPolicy.TYPE_IMAGE)) {
-    channel.asyncOpen(new streamListener("image/png"), null);
-    do_test_pending();
-  }
+                                        Ci.nsIContentPolicy.TYPE_IMAGE);
+  channel.asyncOpen(new streamListener("image/png"), null);
+  do_test_pending();
 
   // Test URI that we don't know anything about.  Will end up being the default
   // icon, so expect image/png.
-  let (channel = ios.newChannel2(moz_anno_favicon_prefix + "http://mozilla.org",
-                                 null,
-                                 null,
-                                 null,      // aLoadingNode
-                                 Services.scriptSecurityManager.getSystemPrincipal(),
-                                 null,      // aTriggeringPrincipal
-                                 Ci.nsILoadInfo.SEC_NORMAL,
-                                 Ci.nsIContentPolicy.TYPE_IMAGE)) {
-    channel.asyncOpen(new streamListener("image/png"), null);
-    do_test_pending();
-  }
+  channel = ios.newChannel2(moz_anno_favicon_prefix + "http://mozilla.org",
+                            null,
+                            null,
+                            null,      // aLoadingNode
+                            Services.scriptSecurityManager.getSystemPrincipal(),
+                            null,      // aTriggeringPrincipal
+                            Ci.nsILoadInfo.SEC_NORMAL,
+                            Ci.nsIContentPolicy.TYPE_IMAGE);
+  channel.asyncOpen(new streamListener("image/png"), null);
+  do_test_pending();
 
   // Test that the content type of a favicon we add ends up being image/png.
-  let (testURI = uri("http://mozilla.org/")) {
-    // Add the data before opening
-    fs.replaceFaviconDataFromDataURL(testURI, testFaviconData,
-                                     (Date.now() + 60 * 60 * 24 * 1000) * 1000);
+  let testURI = uri("http://mozilla.org/");
+  // Add the data before opening
+  fs.replaceFaviconDataFromDataURL(testURI, testFaviconData,
+                                   (Date.now() + 60 * 60 * 24 * 1000) * 1000);
 
-    // Open the channel
-    let channel = ios.newChannel2(moz_anno_favicon_prefix + testURI.spec,
-                                  null,
-                                  null,
-                                  null,      // aLoadingNode
-                                  Services.scriptSecurityManager.getSystemPrincipal(),
-                                  null,      // aTriggeringPrincipal
-                                  Ci.nsILoadInfo.SEC_NORMAL,
-                                  Ci.nsIContentPolicy.TYPE_IMAGE);
-    channel.asyncOpen(new streamListener("image/png"), null);
-    do_test_pending();
-  }
+  // Open the channel
+  channel = ios.newChannel2(moz_anno_favicon_prefix + testURI.spec,
+                            null,
+                            null,
+                            null,      // aLoadingNode
+                            Services.scriptSecurityManager.getSystemPrincipal(),
+                            null,      // aTriggeringPrincipal
+                            Ci.nsILoadInfo.SEC_NORMAL,
+                            Ci.nsIContentPolicy.TYPE_IMAGE);
+  channel.asyncOpen(new streamListener("image/png"), null);
+  do_test_pending();
 }
diff --git a/toolkit/components/places/tests/history/head_history.js b/toolkit/components/places/tests/history/head_history.js
index c47f8d506b02..2632aabcf276 100644
--- a/toolkit/components/places/tests/history/head_history.js
+++ b/toolkit/components/places/tests/history/head_history.js
@@ -12,8 +12,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
-};
-
+}
diff --git a/toolkit/components/places/tests/inline/head_autocomplete.js b/toolkit/components/places/tests/inline/head_autocomplete.js
index 09463a0a2622..7ed53d72a808 100644
--- a/toolkit/components/places/tests/inline/head_autocomplete.js
+++ b/toolkit/components/places/tests/inline/head_autocomplete.js
@@ -10,7 +10,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/migration/head_migration.js b/toolkit/components/places/tests/migration/head_migration.js
index d43a1cf2b445..f4b5abfb2be2 100644
--- a/toolkit/components/places/tests/migration/head_migration.js
+++ b/toolkit/components/places/tests/migration/head_migration.js
@@ -8,7 +8,8 @@ const { classes: Cc, interfaces: Ci, results: Cr, utils: Cu } = Components;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/network/head_network.js b/toolkit/components/places/tests/network/head_network.js
index 3f72dbea8385..d6988c06fa73 100644
--- a/toolkit/components/places/tests/network/head_network.js
+++ b/toolkit/components/places/tests/network/head_network.js
@@ -12,7 +12,8 @@ Cu.import("resource://testing-common/httpd.js");
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/queries/head_queries.js b/toolkit/components/places/tests/queries/head_queries.js
index bf0e33604fc0..4740703a7302 100644
--- a/toolkit/components/places/tests/queries/head_queries.js
+++ b/toolkit/components/places/tests/queries/head_queries.js
@@ -12,7 +12,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/queries/test_async.js b/toolkit/components/places/tests/queries/test_async.js
index 72c64ba39243..b3eeba1a790d 100644
--- a/toolkit/components/places/tests/queries/test_async.js
+++ b/toolkit/components/places/tests/queries/test_async.js
@@ -186,7 +186,8 @@ Test.prototype = {
   openContainer: function () {
     // Set up the result observer.  It delegates to this object's callbacks and
     // wraps them in a try-catch so that errors don't get eaten.
-    this.observer = let (self = this) {
+    let self = this;
+    this.observer = {
       containerStateChanged: function (container, oldState, newState) {
         print("New state passed to containerStateChanged() should equal the " +
               "container's current state");
@@ -230,7 +231,7 @@ Test.prototype = {
    * This must be called before run().  It adds a bookmark and sets up the
    * test's result.  Override if need be.
    */
-  setup: function () {
+  setup: function*() {
     // Populate the database with different types of bookmark items.
     this.data = DataHelper.makeDataArray([
       { type: "bookmark" },
@@ -290,7 +291,8 @@ let DataHelper = {
    * @return An array of objects suitable for passing to populateDB().
    */
   makeDataArray: function DH_makeDataArray(aData) {
-    return let (self = this) aData.map(function (dat) {
+    let self = this;
+    return aData.map(function (dat) {
       let type = dat.type;
       dat = self._makeDataWithDefaults(dat, self.defaults[type]);
       switch (type) {
@@ -348,7 +350,7 @@ function run_test()
   run_next_test();
 }
 
-add_task(function test_async()
+add_task(function* test_async()
 {
   for (let [, test] in Iterator(tests)) {
     remove_all_bookmarks();
diff --git a/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js b/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js
index fd3892b50772..3b192a4d89d5 100644
--- a/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js
+++ b/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js
@@ -10,7 +10,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/unit/head_bookmarks.js b/toolkit/components/places/tests/unit/head_bookmarks.js
index 67582d03b508..2ae00c14aa1e 100644
--- a/toolkit/components/places/tests/unit/head_bookmarks.js
+++ b/toolkit/components/places/tests/unit/head_bookmarks.js
@@ -11,7 +11,8 @@ const Cu = Components.utils;
 Cu.import("resource://gre/modules/Services.jsm");
 
 // Import common head.
-let (commonFile = do_get_file("../head_common.js", false)) {
+{
+  let commonFile = do_get_file("../head_common.js", false);
   let uri = Services.io.newFileURI(commonFile);
   Services.scriptloader.loadSubScript(uri.spec, this);
 }
diff --git a/toolkit/components/places/tests/unit/test_bookmarks_html.js b/toolkit/components/places/tests/unit/test_bookmarks_html.js
index caa304c2b2b1..d0a2a8382de9 100644
--- a/toolkit/components/places/tests/unit/test_bookmarks_html.js
+++ b/toolkit/components/places/tests/unit/test_bookmarks_html.js
@@ -311,17 +311,16 @@ function* checkItem(aExpected, aNode)
             do_check_eq(aNode.uri, aExpected.url)
           break;
         case "icon":
-          let (deferred = Promise.defer(), data) {
-            PlacesUtils.favicons.getFaviconDataForPage(
-              NetUtil.newURI(aExpected.url),
-              function (aURI, aDataLen, aData, aMimeType) {
-                deferred.resolve(aData);
-              });
-            data = yield deferred.promise;
-            let base64Icon = "data:image/png;base64," +
-                             base64EncodeString(String.fromCharCode.apply(String, data));
-            do_check_true(base64Icon == aExpected.icon);
-          }
+          let deferred = Promise.defer();
+          PlacesUtils.favicons.getFaviconDataForPage(
+            NetUtil.newURI(aExpected.url),
+            function (aURI, aDataLen, aData, aMimeType) {
+              deferred.resolve(aData);
+            });
+          let data = yield deferred.promise;
+          let base64Icon = "data:image/png;base64," +
+                           base64EncodeString(String.fromCharCode.apply(String, data));
+          do_check_true(base64Icon == aExpected.icon);
           break;
         case "keyword":
           break;
diff --git a/toolkit/components/places/tests/unit/test_bookmarks_json.js b/toolkit/components/places/tests/unit/test_bookmarks_json.js
index e0c3538311bf..f756c38e710c 100644
--- a/toolkit/components/places/tests/unit/test_bookmarks_json.js
+++ b/toolkit/components/places/tests/unit/test_bookmarks_json.js
@@ -171,17 +171,16 @@ function checkItem(aExpected, aNode) {
             do_check_eq(aNode.uri, aExpected.url);
           break;
         case "icon":
-          let (deferred = Promise.defer(), data) {
-            PlacesUtils.favicons.getFaviconDataForPage(
-              NetUtil.newURI(aExpected.url),
-              function (aURI, aDataLen, aData, aMimeType) {
-                deferred.resolve(aData);
-              });
-            data = yield deferred.promise;
-            let base64Icon = "data:image/png;base64," +
-                             base64EncodeString(String.fromCharCode.apply(String, data));
-            do_check_true(base64Icon == aExpected.icon);
-          }
+          let deferred = Promise.defer();
+          PlacesUtils.favicons.getFaviconDataForPage(
+            NetUtil.newURI(aExpected.url),
+            function (aURI, aDataLen, aData, aMimeType) {
+              deferred.resolve(aData);
+            });
+          let data = yield deferred.promise;
+          let base64Icon = "data:image/png;base64," +
+                           base64EncodeString(String.fromCharCode.apply(String, data));
+          do_check_true(base64Icon == aExpected.icon);
           break;
         case "keyword":
           break;
diff --git a/toolkit/components/places/tests/unit/test_database_replaceOnStartup.js b/toolkit/components/places/tests/unit/test_database_replaceOnStartup.js
index 1b9e258a77ec..655e19340aff 100644
--- a/toolkit/components/places/tests/unit/test_database_replaceOnStartup.js
+++ b/toolkit/components/places/tests/unit/test_database_replaceOnStartup.js
@@ -6,14 +6,13 @@
 
 function run_test() {
   // Ensure that our database doesn't already exist.
-  let (dbFile = gProfD.clone()) {
-    dbFile.append("places.sqlite");
-    do_check_false(dbFile.exists());
-  }
-  let (dbFile = gProfD.clone()) {
-    dbFile.append("places.sqlite.corrupt");
-    do_check_false(dbFile.exists());
-  }
+  let dbFile = gProfD.clone();
+  dbFile.append("places.sqlite");
+  do_check_false(dbFile.exists());
+
+  dbFile = gProfD.clone();
+  dbFile.append("places.sqlite.corrupt");
+  do_check_false(dbFile.exists());
 
   let file = do_get_file("default.sqlite");
   file.copyToFollowingLinks(gProfD, "places.sqlite");
@@ -29,20 +28,19 @@ function run_test() {
   do_check_eq(PlacesUtils.history.databaseStatus,
               PlacesUtils.history.DATABASE_STATUS_CORRUPT);
 
-  let (dbFile = gProfD.clone()) {
-    dbFile.append("places.sqlite");
-    do_check_true(dbFile.exists());
+  dbFile = gProfD.clone();
+  dbFile.append("places.sqlite");
+  do_check_true(dbFile.exists());
 
-    // Check the new database is really a new one.
-    let db = Services.storage.openUnsharedDatabase(file);
-    try {
-      db.executeSimpleSQL("DELETE * FROM test");
-      do_throw("The new database should not have our unique content");
-    } catch(ex) {}
-    db.close();
-  }
-  let (dbFile = gProfD.clone()) {
-    dbFile.append("places.sqlite.corrupt");
-    do_check_true(dbFile.exists());
-  }
-};
+  // Check the new database is really a new one.
+  db = Services.storage.openUnsharedDatabase(file);
+  try {
+    db.executeSimpleSQL("DELETE * FROM test");
+    do_throw("The new database should not have our unique content");
+  } catch(ex) {}
+  db.close();
+
+  dbFile = gProfD.clone();
+  dbFile.append("places.sqlite.corrupt");
+  do_check_true(dbFile.exists());
+}
diff --git a/toolkit/components/places/tests/unit/test_getPlacesInfo.js b/toolkit/components/places/tests/unit/test_getPlacesInfo.js
index 1ae564d729bb..52ed1057765c 100644
--- a/toolkit/components/places/tests/unit/test_getPlacesInfo.js
+++ b/toolkit/components/places/tests/unit/test_getPlacesInfo.js
@@ -28,7 +28,7 @@ function ensurePlacesInfoObjectsAreEqual(a, b) {
   do_check_eq(a.placeId, b.placeId);
 }
 
-function test_getPlacesInfoExistentPlace() {
+function* test_getPlacesInfoExistentPlace() {
   let testURI = NetUtil.newURI("http://www.example.tld");
   yield PlacesTestUtils.addVisits(testURI);
 
@@ -46,7 +46,7 @@ function test_getPlacesInfoExistentPlace() {
 }
 add_task(test_getPlacesInfoExistentPlace);
 
-function test_getPlacesInfoNonExistentPlace() {
+function* test_getPlacesInfoNonExistentPlace() {
   let testURI = NetUtil.newURI("http://www.example_non_existent.tld");
   let getPlacesInfoResult = yield promiseGetPlacesInfo(testURI);
   do_check_eq(getPlacesInfoResult.results.length, 0);
@@ -54,24 +54,22 @@ function test_getPlacesInfoNonExistentPlace() {
 }
 add_task(test_getPlacesInfoNonExistentPlace);
 
-function test_promisedHelper() {
-  let (uri = NetUtil.newURI("http://www.helper_existent_example.tld")) {
-    yield PlacesTestUtils.addVisits(uri);
-    let placeInfo = yield PlacesUtils.promisePlaceInfo(uri);
-    do_check_true(placeInfo instanceof Ci.mozIPlaceInfo);
-  };
+function* test_promisedHelper() {
+  let uri = NetUtil.newURI("http://www.helper_existent_example.tld");
+  yield PlacesTestUtils.addVisits(uri);
+  let placeInfo = yield PlacesUtils.promisePlaceInfo(uri);
+  do_check_true(placeInfo instanceof Ci.mozIPlaceInfo);
 
-  let (uri = NetUtil.newURI("http://www.helper_non_existent_example.tld")) {
-    try {
-      let placeInfo = yield PlacesUtils.promisePlaceInfo(uri);
-      do_throw("PlacesUtils.promisePlaceInfo should have rejected the promise");
-    }
-    catch(ex) { }
-  };
+  uri = NetUtil.newURI("http://www.helper_non_existent_example.tld");
+  try {
+    let placeInfo = yield PlacesUtils.promisePlaceInfo(uri);
+    do_throw("PlacesUtils.promisePlaceInfo should have rejected the promise");
+  }
+  catch(ex) { }
 }
 add_task(test_promisedHelper);
 
-function test_infoByGUID() {
+function* test_infoByGUID() {
   let testURI = NetUtil.newURI("http://www.guid_example.tld");
   yield PlacesTestUtils.addVisits(testURI);
 
@@ -81,7 +79,7 @@ function test_infoByGUID() {
 }
 add_task(test_infoByGUID);
 
-function test_invalid_guid() {
+function* test_invalid_guid() {
   try {
     let placeInfoByGUID = yield PlacesUtils.promisePlaceInfo("###");
     do_throw("getPlacesInfo should fail for invalid guids")
@@ -90,17 +88,15 @@ function test_invalid_guid() {
 }
 add_task(test_invalid_guid);
 
-function test_mixed_selection() {
+function* test_mixed_selection() {
   let placeInfo1, placeInfo2;
-  let (uri = NetUtil.newURI("http://www.mixed_selection_test_1.tld")) {
-    yield PlacesTestUtils.addVisits(uri);
-    placeInfo1 = yield PlacesUtils.promisePlaceInfo(uri);
-  };
+  let uri = NetUtil.newURI("http://www.mixed_selection_test_1.tld");
+  yield PlacesTestUtils.addVisits(uri);
+  placeInfo1 = yield PlacesUtils.promisePlaceInfo(uri);
 
-  let (uri = NetUtil.newURI("http://www.mixed_selection_test_2.tld")) {
-    yield PlacesTestUtils.addVisits(uri);
-    placeInfo2 = yield PlacesUtils.promisePlaceInfo(uri);
-  };
+  uri = NetUtil.newURI("http://www.mixed_selection_test_2.tld");
+  yield PlacesTestUtils.addVisits(uri);
+  placeInfo2 = yield PlacesUtils.promisePlaceInfo(uri);
 
   let getPlacesInfoResult = yield promiseGetPlacesInfo([placeInfo1.uri, placeInfo2.guid]);
   do_check_eq(getPlacesInfoResult.results.length, 2);
diff --git a/toolkit/components/places/tests/unit/test_tagging.js b/toolkit/components/places/tests/unit/test_tagging.js
index bd6bd7f876df..77a5c63d041d 100644
--- a/toolkit/components/places/tests/unit/test_tagging.js
+++ b/toolkit/components/places/tests/unit/test_tagging.js
@@ -117,61 +117,60 @@ function run_test() {
   do_check_true(uri4Tags.indexOf("456") != -1);
 
   // Test sparse arrays.
-  let (curChildCount = tagRoot.childCount) {
-    try {
-      tagssvc.tagURI(uri1, [, "tagSparse"]);
-      do_check_eq(tagRoot.childCount, curChildCount + 1);
-    } catch (ex) {
-      do_throw("Passing a sparse array should not throw");
-    }
-    try {
-      tagssvc.untagURI(uri1, [, "tagSparse"]);
-      do_check_eq(tagRoot.childCount, curChildCount);
-    } catch (ex) {
-      do_throw("Passing a sparse array should not throw");
-    }
+  let curChildCount = tagRoot.childCount;
 
-    // Test that the API throws for bad arguments.
-    try {
-      tagssvc.tagURI(uri1, ["", "test"]);
-      do_throw("Passing a bad tags array should throw");
-    } catch (ex) {
-      do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
-    }
-    try {
-      tagssvc.untagURI(uri1, ["", "test"]);
-      do_throw("Passing a bad tags array should throw");
-    } catch (ex) {
-      do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
-    }
-    try {
-      tagssvc.tagURI(uri1, [0, "test"]);
-      do_throw("Passing a bad tags array should throw");
-    } catch (ex) {
-      do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
-    }
-    try {
-      tagssvc.tagURI(uri1, [0, "test"]);
-      do_throw("Passing a bad tags array should throw");
-    } catch (ex) {
-      do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
-    }
-    
-    // Tag name length should be limited to nsITaggingService.MAX_TAG_LENGTH (bug407821)
-    try {
-    
-      // generate a long tag name. i.e. looooo...oong_tag
-      var n = Ci.nsITaggingService.MAX_TAG_LENGTH;
-      var someOos = new Array(n).join('o');
-      var longTagName = "l" + someOos + "ng_tag";
-      
-      tagssvc.tagURI(uri1, ["short_tag", longTagName]);
-      do_throw("Passing a bad tags array should throw");
-      
-    } catch (ex) {
-      do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
-    }
-    
+  try {
+    tagssvc.tagURI(uri1, [, "tagSparse"]);
+    do_check_eq(tagRoot.childCount, curChildCount + 1);
+  } catch (ex) {
+    do_throw("Passing a sparse array should not throw");
+  }
+  try {
+    tagssvc.untagURI(uri1, [, "tagSparse"]);
+    do_check_eq(tagRoot.childCount, curChildCount);
+  } catch (ex) {
+    do_throw("Passing a sparse array should not throw");
+  }
+
+  // Test that the API throws for bad arguments.
+  try {
+    tagssvc.tagURI(uri1, ["", "test"]);
+    do_throw("Passing a bad tags array should throw");
+  } catch (ex) {
+    do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
+  }
+  try {
+    tagssvc.untagURI(uri1, ["", "test"]);
+    do_throw("Passing a bad tags array should throw");
+  } catch (ex) {
+    do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
+  }
+  try {
+    tagssvc.tagURI(uri1, [0, "test"]);
+    do_throw("Passing a bad tags array should throw");
+  } catch (ex) {
+    do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
+  }
+  try {
+    tagssvc.tagURI(uri1, [0, "test"]);
+    do_throw("Passing a bad tags array should throw");
+  } catch (ex) {
+    do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
+  }
+
+  // Tag name length should be limited to nsITaggingService.MAX_TAG_LENGTH (bug407821)
+  try {
+
+    // generate a long tag name. i.e. looooo...oong_tag
+    var n = Ci.nsITaggingService.MAX_TAG_LENGTH;
+    var someOos = new Array(n).join('o');
+    var longTagName = "l" + someOos + "ng_tag";
+
+    tagssvc.tagURI(uri1, ["short_tag", longTagName]);
+    do_throw("Passing a bad tags array should throw");
+
+  } catch (ex) {
+    do_check_eq(ex.name, "NS_ERROR_ILLEGAL_VALUE");
   }
 
   // cleanup
diff --git a/toolkit/modules/tests/xpcshell/test_dict.js b/toolkit/modules/tests/xpcshell/test_dict.js
index c07fb5395a70..66f49aef2640 100644
--- a/toolkit/modules/tests/xpcshell/test_dict.js
+++ b/toolkit/modules/tests/xpcshell/test_dict.js
@@ -189,67 +189,62 @@ function test_set_property_lazy_getter() {
     });
   };
 
-  let (dict = new Dict()) {
-    setThunk(dict);
+  let dict = new Dict();
+  setThunk(dict);
 
-    // Test that checking for the key existence does not invoke
-    // the getter function.
-    do_check_true(dict.has("foo"));
-    do_check_false(thunkCalled);
-    do_check_true(dict.isLazyGetter("foo"));
+  // Test that checking for the key existence does not invoke
+  // the getter function.
+  do_check_true(dict.has("foo"));
+  do_check_false(thunkCalled);
+  do_check_true(dict.isLazyGetter("foo"));
 
-    // Calling get the first time should invoke the getter function
-    // and unmark the key as a lazy getter.
-    do_check_eq(dict.get("foo"), "bar");
-    do_check_true(thunkCalled);
-    do_check_false(dict.isLazyGetter("foo"));
+  // Calling get the first time should invoke the getter function
+  // and unmark the key as a lazy getter.
+  do_check_eq(dict.get("foo"), "bar");
+  do_check_true(thunkCalled);
+  do_check_false(dict.isLazyGetter("foo"));
 
-    // Calling get again should not invoke the getter function
-    thunkCalled = false;
-    do_check_eq(dict.get("foo"), "bar");
-    do_check_false(thunkCalled);
-    do_check_false(dict.isLazyGetter("foo"));
-  }
+  // Calling get again should not invoke the getter function
+  thunkCalled = false;
+  do_check_eq(dict.get("foo"), "bar");
+  do_check_false(thunkCalled);
+  do_check_false(dict.isLazyGetter("foo"));
 
   // Test that listvalues works for lazy keys.
-  let (dict = new Dict()) {
-    setThunk(dict);
-    do_check_true(dict.isLazyGetter("foo"));
+  dict = new Dict();
+  setThunk(dict);
+  do_check_true(dict.isLazyGetter("foo"));
 
-    let (listvalues = dict.listvalues()) {
-      do_check_false(dict.isLazyGetter("foo"));
-      do_check_true(thunkCalled);
-      do_check_true(listvalues.length, 1);
-      do_check_eq(listvalues[0], "bar");
-    }
+  let listvalues = dict.listvalues();
+  do_check_false(dict.isLazyGetter("foo"));
+  do_check_true(thunkCalled);
+  do_check_true(listvalues.length, 1);
+  do_check_eq(listvalues[0], "bar");
 
-    thunkCalled = false;
+  thunkCalled = false;
 
-    // Retrieving the list again shouldn't invoke our getter.
-    let (listvalues = dict.listvalues()) {
-      do_check_false(dict.isLazyGetter("foo"));
-      do_check_false(thunkCalled);
-      do_check_true(listvalues.length, 1);
-      do_check_eq(listvalues[0], "bar");
-    }
-  }
+  // Retrieving the list again shouldn't invoke our getter.
+  listvalues = dict.listvalues();
+  do_check_false(dict.isLazyGetter("foo"));
+  do_check_false(thunkCalled);
+  do_check_true(listvalues.length, 1);
+  do_check_eq(listvalues[0], "bar");
 
   // Test that the values iterator also works as expected.
-  let (dict = new Dict()) {
-    setThunk(dict);
-    let values = dict.values;
+  dict = new Dict();
+  setThunk(dict);
+  let values = dict.values;
 
-    // Our getter shouldn't be called before the iterator reaches it.
-    do_check_true(dict.isLazyGetter("foo"));
-    do_check_false(thunkCalled);
-    do_check_eq(values.next(), "bar");
-    do_check_true(thunkCalled);
+  // Our getter shouldn't be called before the iterator reaches it.
+  do_check_true(dict.isLazyGetter("foo"));
+  do_check_false(thunkCalled);
+  do_check_eq(values.next(), "bar");
+  do_check_true(thunkCalled);
 
-    thunkCalled = false;
-    do_check_false(dict.isLazyGetter("foo"));
-    do_check_eq(dict.get("foo"), "bar");
-    do_check_false(thunkCalled);
-  }
+  thunkCalled = false;
+  do_check_false(dict.isLazyGetter("foo"));
+  do_check_eq(dict.get("foo"), "bar");
+  do_check_false(thunkCalled);
 }
 
 // This is used by both test_construct_dict_from_json_string and test_serialize_dict_to_json_string
diff --git a/toolkit/modules/tests/xpcshell/test_propertyListsUtils.js b/toolkit/modules/tests/xpcshell/test_propertyListsUtils.js
index 0787e1e171fe..6db28ae240e0 100644
--- a/toolkit/modules/tests/xpcshell/test_propertyListsUtils.js
+++ b/toolkit/modules/tests/xpcshell/test_propertyListsUtils.js
@@ -36,47 +36,45 @@ function checkMainPropertyList(aPropertyListRoot) {
 
   checkValue(aPropertyListRoot, PropertyListUtils.TYPE_DICTIONARY);
   checkValue(aPropertyListRoot.get("Boolean"), PRIMITIVE, false);
-  let (array = aPropertyListRoot.get("Array")) {
-    checkValue(array, PropertyListUtils.TYPE_ARRAY);
-    do_check_eq(array.length, 8);
+  let array = aPropertyListRoot.get("Array");
+  checkValue(array, PropertyListUtils.TYPE_ARRAY);
+  do_check_eq(array.length, 8);
 
-    // Test both long and short values, since binary property lists store
-    // long values a little bit differently (see readDataLengthAndOffset).
+  // Test both long and short values, since binary property lists store
+  // long values a little bit differently (see readDataLengthAndOffset).
 
-    // Short ASCII string
-    checkLazyGetterValue(array, 0, PRIMITIVE, "abc");
-    // Long ASCII string
-    checkLazyGetterValue(array, 1, PRIMITIVE, new Array(1001).join("a"));
-    // Short unicode string
-    checkLazyGetterValue(array, 2, PRIMITIVE, "\u05D0\u05D0\u05D0");
-    // Long unicode string
-    checkLazyGetterValue(array, 3, PRIMITIVE, new Array(1001).join("\u05D0"));
-    // Unicode surrogate pair
-    checkLazyGetterValue(array, 4, PRIMITIVE,
-                         "\uD800\uDC00\uD800\uDC00\uD800\uDC00");
+  // Short ASCII string
+  checkLazyGetterValue(array, 0, PRIMITIVE, "abc");
+  // Long ASCII string
+  checkLazyGetterValue(array, 1, PRIMITIVE, new Array(1001).join("a"));
+  // Short unicode string
+  checkLazyGetterValue(array, 2, PRIMITIVE, "\u05D0\u05D0\u05D0");
+  // Long unicode string
+  checkLazyGetterValue(array, 3, PRIMITIVE, new Array(1001).join("\u05D0"));
+  // Unicode surrogate pair
+  checkLazyGetterValue(array, 4, PRIMITIVE,
+                       "\uD800\uDC00\uD800\uDC00\uD800\uDC00");
 
-    // Date
-    checkLazyGetterValue(array, 5, PropertyListUtils.TYPE_DATE,
-                         new Date("2011-12-31T11:15:23Z"));
+  // Date
+  checkLazyGetterValue(array, 5, PropertyListUtils.TYPE_DATE,
+                       new Date("2011-12-31T11:15:23Z"));
 
-    // Data
-    checkLazyGetterValue(array, 6, PropertyListUtils.TYPE_UINT8_ARRAY);
-    let dataAsString = [String.fromCharCode(b) for each (b in array[6])].join("");
-    do_check_eq(dataAsString, "2011-12-31T11:15:33Z");
+  // Data
+  checkLazyGetterValue(array, 6, PropertyListUtils.TYPE_UINT8_ARRAY);
+  let dataAsString = [String.fromCharCode(b) for each (b in array[6])].join("");
+  do_check_eq(dataAsString, "2011-12-31T11:15:33Z");
 
-    // Dict
-    let (dict = array[7]) {
-      checkValue(dict, PropertyListUtils.TYPE_DICTIONARY);
-      checkValue(dict.get("Negative Number"), PRIMITIVE, -400);
-      checkValue(dict.get("Real Number"), PRIMITIVE, 2.71828183);
-      checkValue(dict.get("Big Int"),
-                 PropertyListUtils.TYPE_INT64,
-                 "9007199254740993");
-      checkValue(dict.get("Negative Big Int"),
-                 PropertyListUtils.TYPE_INT64,
-                 "-9007199254740993");
-    }
-  }
+  // Dict
+  let dict = array[7];
+  checkValue(dict, PropertyListUtils.TYPE_DICTIONARY);
+  checkValue(dict.get("Negative Number"), PRIMITIVE, -400);
+  checkValue(dict.get("Real Number"), PRIMITIVE, 2.71828183);
+  checkValue(dict.get("Big Int"),
+             PropertyListUtils.TYPE_INT64,
+             "9007199254740993");
+  checkValue(dict.get("Negative Big Int"),
+             PropertyListUtils.TYPE_INT64,
+             "-9007199254740993");
 }
 
 function readPropertyList(aFile, aCallback) {