Be explicit about namespace testing to not mix it with blink::testing

third_party/WebKit/Source/web/tests/LocalFrameClientImplTest.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 23 matching lines @@
 #include "core/frame/WebLocalFrameBase.h"
 #include "platform/weborigin/KURL.h"
 #include "platform/wtf/text/CString.h"
 #include "platform/wtf/text/WTFString.h"
 #include "public/web/WebFrameClient.h"
 #include "public/web/WebSettings.h"
 #include "public/web/WebView.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-using testing::_;
-using testing::Mock;
-using testing::Return;
+using ::testing::_;
+using ::testing::Mock;
+using ::testing::Return;
 
 namespace blink {
 namespace {
 
 class MockWebFrameClient : public FrameTestHelpers::TestWebFrameClient {
  public:
   ~MockWebFrameClient() override {}
 
   MOCK_METHOD0(UserAgentOverride, WebString());
 };
@@ skipping 47 matching lines @@
   Mock::VerifyAndClearExpectations(&WebFrameClient());
 
   // Remove the override and make sure we get the original back.
   EXPECT_CALL(WebFrameClient(), UserAgentOverride())
       .WillOnce(Return(WebString()));
   EXPECT_TRUE(default_user_agent.Equals(UserAgent()));
 }
 
 }  // namespace
 }  // namespace blink