Remove PluginLoadObserver and related logic, it was only used for NPAPI.

content/renderer/browser_plugin/browser_plugin.h

 // Copyright 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.
 
 #ifndef CONTENT_RENDERER_BROWSER_PLUGIN_BROWSER_PLUGIN_H_
 #define CONTENT_RENDERER_BROWSER_PLUGIN_BROWSER_PLUGIN_H_
 
 #include "third_party/WebKit/public/web/WebPlugin.h"
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 90 matching lines @@
                         blink::WebCursorInfo& cursor_info) override;
   bool handleDragStatusUpdate(blink::WebDragStatus drag_status,
                               const blink::WebDragData& drag_data,
                               blink::WebDragOperationsMask mask,
                               const blink::WebPoint& position,
                               const blink::WebPoint& screen) override;
   void didReceiveResponse(const blink::WebURLResponse& response) override;
   void didReceiveData(const char* data, int data_length) override;
   void didFinishLoading() override;
   void didFailLoading(const blink::WebURLError& error) override;
-  void didFinishLoadingFrameRequest(const blink::WebURL& url,
-                                    void* notify_data) override;
-  void didFailLoadingFrameRequest(const blink::WebURL& url,
-                                  void* notify_data,
-                                  const blink::WebURLError& error) override;
   bool executeEditCommand(const blink::WebString& name) override;
   bool executeEditCommand(const blink::WebString& name,
                           const blink::WebString& value) override;
   bool setComposition(
       const blink::WebString& text,
       const blink::WebVector<blink::WebCompositionUnderline>& underlines,
       int selectionStart,
       int selectionEnd) override;
   bool confirmComposition(
       const blink::WebString& text,
@@ skipping 85 matching lines @@
   // Weak factory used in v8 |MakeWeak| callback, since the v8 callback might
   // get called after BrowserPlugin has been destroyed.
   base::WeakPtrFactory<BrowserPlugin> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPlugin);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_BROWSER_PLUGIN_BROWSER_PLUGIN_H_