Use ScopedTaskEnvironment instead of MessageLoop in content unit tests.

content/browser/quota/usage_tracker_unittest.cc

 // Copyright 2014 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 <stdint.h>
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
+#include "base/test/scoped_task_environment.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "content/public/test/mock_special_storage_policy.h"
 #include "net/base/url_util.h"
 #include "storage/browser/quota/usage_tracker.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using storage::kQuotaStatusOk;
 using storage::kStorageTypeTemporary;
 using storage::QuotaClient;
 using storage::QuotaClientList;
@@ skipping 176 matching lines @@
         quota_client_.id(), origin, enabled);
   }
 
  private:
   QuotaClientList GetUsageTrackerList() {
     QuotaClientList client_list;
     client_list.push_back(&quota_client_);
     return client_list;
   }
 
-  base::MessageLoop message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
 
   scoped_refptr<MockSpecialStoragePolicy> storage_policy_;
   MockQuotaClient quota_client_;
   UsageTracker usage_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(UsageTrackerTest);
 };
 
 TEST_F(UsageTrackerTest, GrantAndRevokeUnlimitedStorage) {
   int64_t usage = 0;
@@ skipping 110 matching lines @@
 
   GetGlobalLimitedUsage(&limited_usage);
   GetGlobalUsage(&total_usage, &unlimited_usage);
   EXPECT_EQ(1 + 16, limited_usage);
   EXPECT_EQ(1 + 2 + 16 + 32, total_usage);
   EXPECT_EQ(2 + 32, unlimited_usage);
 }
 
 
 }  // namespace content