mojo/public: Include gtest.h as "gtest/gtest.h", instead of via "absolute" path.

mojo/public/cpp/utility/tests/run_loop_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 "mojo/public/cpp/utility/run_loop.h"
 
 #include <string>
 
+#include "gtest/gtest.h"
 #include "mojo/public/cpp/system/macros.h"
 #include "mojo/public/cpp/system/message_pipe.h"
 #include "mojo/public/cpp/test_support/test_utils.h"
 #include "mojo/public/cpp/utility/run_loop_handler.h"
-#include "testing/gtest/include/gtest/gtest.h"
 
 namespace mojo {
 namespace {
 
 class TestRunLoopHandler : public RunLoopHandler {
  public:
   TestRunLoopHandler() {}
   ~TestRunLoopHandler() override {}
 
   void clear_ready_count() { ready_count_ = 0; }
@@ skipping 402 matching lines @@
   run_loop.AddHandler(&handler,
                       test_pipe.handle0.get(),
                       MOJO_HANDLE_SIGNAL_READABLE,
                       MOJO_DEADLINE_INDEFINITE);
   run_loop.PostDelayedTask(Closure(QuittingTask(&run_loop)), 0);
   run_loop.Run();
 }
 
 }  // namespace
 }  // namespace mojo