Don't include headers from the layout API from other headers needlessly.

third_party/WebKit/Source/web/WebPluginContainerImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2014 Opera Software ASA. 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.
@@ skipping 40 matching lines @@
 #include "core/frame/EventHandlerRegistry.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/html/HTMLFormElement.h"
 #include "core/html/HTMLPlugInElement.h"
 #include "core/input/EventHandler.h"
 #include "core/layout/HitTestResult.h"
 #include "core/layout/LayoutBox.h"
 #include "core/layout/LayoutView.h"
+#include "core/layout/api/LayoutPartItem.h"
+#include "core/layout/api/LayoutViewItem.h"
 #include "core/loader/FrameLoadRequest.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/paint/LayoutObjectDrawingRecorder.h"
 #include "core/paint/PaintLayer.h"
 #include "modules/plugins/PluginOcclusionSupport.h"
 #include "platform/HostWindow.h"
 #include "platform/KeyboardCodes.h"
 #include "platform/PlatformGestureEvent.h"
@@ skipping 866 matching lines @@
         // frame view.
         computeClipRectsForPlugin(m_element, windowRect, clipRect, unobscuredRect);
     }
     getPluginOcclusions(m_element, this->parent(), frameRect(), cutOutRects);
     // Convert to the plugin position.
     for (size_t i = 0; i < cutOutRects.size(); i++)
         cutOutRects[i].move(-frameRect().x(), -frameRect().y());
 }
 
 } // namespace blink