Introduce WebPluginContainerBase to abstract WebPluginContainerImpl.

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 647 matching lines @@
 }
 
 bool WebPluginContainerImpl::WantsWheelEvents() {
   return wants_wheel_events_;
 }
 
 // Private methods -------------------------------------------------------------
 
 WebPluginContainerImpl::WebPluginContainerImpl(HTMLPlugInElement* element,
                                                WebPlugin* web_plugin)
-    : ContextClient(element->GetDocument().GetFrame()),
+    : WebPluginContainerBase(element->GetDocument().GetFrame()),
       element_(element),
       web_plugin_(web_plugin),
       web_layer_(nullptr),
       touch_event_request_type_(kTouchEventRequestTypeNone),
       wants_wheel_events_(false),
       self_visible_(false),
       parent_visible_(false),
       is_disposed_(false) {}
 
 WebPluginContainerImpl::~WebPluginContainerImpl() {
@@ skipping 15 matching lines @@
 
   if (web_layer_) {
     GraphicsLayer::UnregisterContentsLayer(web_layer_);
     web_layer_ = nullptr;
   }
 }
 
 DEFINE_TRACE(WebPluginContainerImpl) {
   visitor->Trace(parent_);
   visitor->Trace(element_);
-  ContextClient::Trace(visitor);
-  PluginView::Trace(visitor);
+  WebPluginContainerBase::Trace(visitor);
 }
 
 void WebPluginContainerImpl::HandleMouseEvent(MouseEvent* event) {
   // We cache the parent FrameView here as the plugin widget could be deleted
   // in the call to HandleEvent. See http://b/issue?id=1362948
   FrameView* parent_view = parent_;
 
   // TODO(dtapuska): Move WebMouseEventBuilder into the anonymous namespace
   // in this class.
   WebMouseEventBuilder transformed_event(
@@ skipping 310 matching lines @@
            .GetLayoutViewItem()
            .IsNull()) {
     // Take our element and get the clip rect from the enclosing layer and
     // frame view.
     ComputeClipRectsForPlugin(element_, window_rect, clip_rect,
                               unobscured_rect);
   }
 }
 
 }  // namespace blink