Migrate content/ files to histogram_macros.h includes.

content/renderer/gamepad_shared_memory_reader.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 "content/renderer/gamepad_shared_memory_reader.h"
 
-#include "base/metrics/histogram.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/trace_event/trace_event.h"
 #include "content/common/gamepad_hardware_buffer.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/renderer/renderer_blink_platform_impl.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "third_party/WebKit/public/platform/WebGamepadListener.h"
 #include "third_party/WebKit/public/platform/WebPlatformEventListener.h"
 
 namespace content {
 
@@ skipping 111 matching lines @@
 }
 
 void GamepadSharedMemoryReader::OnGamepadDisconnected(
     int index,
     const blink::WebGamepad& gamepad) {
   if (listener())
     listener()->didDisconnectGamepad(index, gamepad);
 }
 
 } // namespace content