pepper: Use the RenderThread's shared context as the parent context.

content/renderer/pepper/pepper_plugin_delegate_impl.h

Index: content/renderer/pepper/pepper_plugin_delegate_impl.h
diff --git a/content/renderer/pepper/pepper_plugin_delegate_impl.h b/content/renderer/pepper/pepper_plugin_delegate_impl.h
index 67a3438c97bc7cf94708fd00f1e203ac05c93ee0..5a6621406d3c5c061f4fe74e4671eccd3947722e 100644
--- a/content/renderer/pepper/pepper_plugin_delegate_impl.h
+++ b/content/renderer/pepper/pepper_plugin_delegate_impl.h
@@ -18,7 +18,6 @@
 #include "base/observer_list.h"
 #include "content/public/renderer/render_view_observer.h"
 #include "content/renderer/mouse_lock_dispatcher.h"
-#include "content/renderer/pepper/pepper_parent_context_provider.h"
 #include "content/renderer/render_view_pepper_helper.h"
 #include "ppapi/shared_impl/private/ppb_tcp_server_socket_shared.h"
 #include "ppapi/shared_impl/private/tcp_socket_private_impl.h"
@@ -63,7 +62,6 @@ class PepperPluginDelegateImpl
     : public webkit::ppapi::PluginDelegate,
       public RenderViewPepperHelper,
       public base::SupportsWeakPtr<PepperPluginDelegateImpl>,
-      public PepperParentContextProvider,
       public RenderViewObserver {
  public:
   explicit PepperPluginDelegateImpl(RenderViewImpl* render_view);
@@ -382,10 +380,6 @@ class PepperPluginDelegateImpl
       int plugin_child_id,
       bool is_external);
 
-  // Implementation of PepperParentContextProvider.
-  virtual WebGraphicsContext3DCommandBufferImpl*
-      GetParentContextForPlatformContext3D() OVERRIDE;
-
   MouseLockDispatcher::LockTarget* GetOrCreateLockTargetAdapter(
       webkit::ppapi::PluginInstance* instance);
   void UnSetAndDeleteLockTargetAdapter(webkit::ppapi::PluginInstance* instance);