Introduce the abstract class WebViewBase, to decouple WebViewImpl.

third_party/WebKit/Source/web/WebLocalFrameImpl.h

 /*
  * Copyright (C) 2009 Google Inc. 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 54 matching lines @@
 class WebDevToolsAgentImpl;
 class WebDevToolsFrontendImpl;
 class WebFrameClient;
 class WebInputMethodControllerImpl;
 class WebNode;
 class WebPerformance;
 class WebPlugin;
 class WebPluginContainerImpl;
 class WebScriptExecutionCallback;
 class WebView;
-class WebViewImpl;
+class WebViewBase;
 enum class WebFrameLoadType;
 struct FrameLoadRequest;
 struct WebContentSecurityPolicyViolation;
 struct WebPrintParams;
 
 template <typename T>
 class WebVector;
 
 // Implementation of WebFrame, note that this is a reference counted object.
 class WEB_EXPORT WebLocalFrameImpl final
@@ skipping 266 matching lines @@
   // WebPluginContainerImpl that hosts the plugin.
   static WebPluginContainerImpl* PluginContainerFromFrame(LocalFrame*);
 
   // If the frame hosts a PluginDocument, this method returns the
   // WebPluginContainerImpl that hosts the plugin. If the provided node is a
   // plugin, then it runs its WebPluginContainerImpl. Otherwise, uses the
   // currently focused element (if any).
   static WebPluginContainerImpl* CurrentPluginContainer(LocalFrame*,
                                                         Node* = nullptr);
 
-  WebViewImpl* ViewImpl() const;
+  WebViewBase* ViewImpl() const;
 
   FrameView* GetFrameView() const {
     return GetFrame() ? GetFrame()->View() : 0;
   }
 
   WebDevToolsAgentImpl* DevToolsAgentImpl() const {
     return dev_tools_agent_.Get();
   }
 
   // Getters for the impls corresponding to Get(Provisional)DataSource. They
@@ skipping 145 matching lines @@
 
 DEFINE_TYPE_CASTS(WebLocalFrameImpl,
                   WebFrame,
                   frame,
                   frame->IsWebLocalFrame(),
                   frame.IsWebLocalFrame());
 
 }  // namespace blink
 
 #endif