Fix mem leak in sync tests by ensuring that the destruction tasks get to run....

chrome/browser/sync/profile_sync_service_unittest.cc

 // Copyright (c) 2006-2008 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 <stack>
 #include <vector>
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 #include "base/command_line.h"
+#include "base/message_loop.h"
 #include "base/string_util.h"
 #include "base/string16.h"
 #include "chrome/browser/bookmarks/bookmark_model.h"
 #include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/sync/engine/syncapi.h"
 #include "chrome/browser/sync/glue/model_associator.h"
 #include "chrome/browser/sync/glue/sync_backend_host.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/common/chrome_switches.h"
@@ skipping 251 matching lines @@
       : ui_thread_(ChromeThread::UI, &message_loop_),
         file_thread_(ChromeThread::FILE, &message_loop_),
         model_(NULL) {
     profile_.reset(new TestingProfile());
     profile_->set_has_history_service(true);
   }
   virtual ~ProfileSyncServiceTest() {
     // Kill the service before the profile.
     service_.reset();
     profile_.reset();
+
+    // Ensure that the sync objects destruct to avoid memory leaks.
+    MessageLoop::current()->RunAllPending();

[tim (not reviewing), 2009/11/03 00:12:11]

I'm just a little confused if this works, because the task in question
(RegistrationTask in extensions_activity_monitor.cc) dereferences a
NotificationRegistrar that I would have imagined was deleted by the above
reset()s... ?

[jam, 2009/11/03 00:16:13]

That's not the task in question.  That task already ran, that's why there's the
leak.  The task that this pumps is the one that leads to
ExtensionsActivityMonitor's destructor running.

   }
 
   ModelAssociator* associator() {
     DCHECK(service_.get());
     return service_->model_associator_;
   }
 
   ChangeProcessingInterface* change_processor() {
     DCHECK(service_.get());
     return service_->change_processor_.get();
@@ skipping 1007 matching lines @@
 
   // Restart the sync service.
   StartSyncService();
 
   // Make sure we're back in sync.  In real life, the user would need
   // to reauthenticate before this happens, but in the test, authentication
   // is sidestepped.
   ExpectBookmarkModelMatchesTestData();
   ExpectModelMatch();
 }