content: Cleanup class/struct forward declarations

content/browser/renderer_host/input/web_input_event_builders_android.h

 // Copyright 2013 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_WEB_INPUT_EVENT_BUILDERS_ANDROID_H_
 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_WEB_INPUT_EVENT_BUILDERS_ANDROID_H_
 
 #include <jni.h>
 
 #include "base/android/scoped_java_ref.h"
 #include "content/common/content_export.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 
-namespace ui {
-class MotionEventAndroid;
-}
-
 namespace content {
 
 class WebMouseEventBuilder {
  public:
   static blink::WebMouseEvent Build(
       blink::WebInputEvent::Type type,
       blink::WebMouseEvent::Button button,
       double time_sec,
       int window_x,
       int window_y,
@@ skipping 30 matching lines @@
  public:
   static blink::WebGestureEvent Build(blink::WebInputEvent::Type type,
                                       double time_sec,
                                       int x,
                                       int y);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_WEB_INPUT_EVENT_BUILDERS_ANDROID_H_