Mac: Correctly show/hide compositor on navigations.

chrome/renderer/webgles2context_impl.h

 // Copyright (c) 2010 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 CHROME_RENDERER_WEBGLES2CONTEXT_IMPL_H_
 #define CHROME_RENDERER_WEBGLES2CONTEXT_IMPL_H_
 #pragma once
 
 #if defined(ENABLE_GPU)
 
 #include "chrome/renderer/ggl/ggl.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebGLES2Context.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebSize.h"
 
+#if defined(OS_MACOSX)
+#include "gfx/native_widget_types.h"
+#endif
+
 class WebGLES2ContextImpl : public WebKit::WebGLES2Context {
  public:
   WebGLES2ContextImpl();
   virtual ~WebGLES2ContextImpl();
 
   // TODO(vangelis): Remove once method is removed from WebGLES2Context.
   virtual bool initialize(WebKit::WebView*);
   virtual bool initialize(WebKit::WebView*, WebGLES2Context* parent);
   virtual bool makeCurrent();
   virtual bool destroy();
   virtual bool swapBuffers();
 
   virtual void resizeOffscreenContent(const WebKit::WebSize&);
   virtual unsigned getOffscreenContentParentTextureId();
 
 #if defined(OS_MACOSX)
   virtual void resizeOnscreenContent(const WebKit::WebSize&);
 #endif
 
   ggl::Context* context() { return context_; }
 
  private:
   // The GGL context we use for OpenGL rendering.
   ggl::Context* context_;
+
+#if defined(OS_MACOSX)
+  gfx::PluginWindowHandle plugin_handle_;
   WebKit::WebView* web_view_;
+#endif
 };
 
 #endif  // defined(ENABLE_GPU)
 #endif  // CHROME_RENDERER_WEBGLES2CONTEXT_IMPL_H_