[Sync] Make P2PNotifier emit a notification only if some enabled types changed

chrome/browser/sync/test/integration/two_client_extensions_sync_test.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/basictypes.h"
 #include "chrome/browser/sync/profile_sync_service_harness.h"
 #include "chrome/browser/sync/test/integration/extensions_helper.h"
 #include "chrome/browser/sync/test/integration/sync_test.h"
 
 using extensions_helper::AllProfilesHaveSameExtensionsAsVerifier;
@@ skipping 229 matching lines @@
 }
 
 // TCM ID - 3732278.
 IN_PROC_BROWSER_TEST_F(TwoClientExtensionsSyncTest, DisableExtensions) {
   ASSERT_TRUE(SetupSync());
   ASSERT_TRUE(AllProfilesHaveSameExtensionsAsVerifier());
 
   ASSERT_TRUE(GetClient(1)->DisableSyncForDatatype(syncer::EXTENSIONS));
   InstallExtension(GetProfile(0), 1);
   InstallExtension(verifier(), 1);
-  ASSERT_TRUE(AwaitQuiescence());
+  ASSERT_TRUE(
+      GetClient(0)->AwaitFullSyncCompletion("Installed an extension."));
   ASSERT_FALSE(AllProfilesHaveSameExtensionsAsVerifier());
 
   ASSERT_TRUE(GetClient(1)->EnableSyncForDatatype(syncer::EXTENSIONS));
   ASSERT_TRUE(AwaitQuiescence());
   InstallExtensionsPendingForSync(GetProfile(0));
   InstallExtensionsPendingForSync(GetProfile(1));
   InstallExtensionsPendingForSync(verifier());
   ASSERT_TRUE(AllProfilesHaveSameExtensionsAsVerifier());
 }
 
@@ skipping 37 matching lines @@
 
   UninstallExtension(GetProfile(0), 0);
   UninstallExtension(verifier(), 0);
 
   ASSERT_TRUE(AwaitQuiescence());
   ASSERT_TRUE(AllProfilesHaveSameExtensionsAsVerifier());
 }
 
 // TODO(akalin): Add tests exercising:
 //   - Offline installation/uninstallation behavior