Plugin Power Saver: Add UI Overlay to throttled plugin using placeholder.

content/renderer/pepper/pepper_plugin_instance_impl.h

 // Copyright (c) 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_PEPPER_PEPPER_PLUGIN_INSTANCE_IMPL_H_
 #define CONTENT_RENDERER_PEPPER_PEPPER_PLUGIN_INSTANCE_IMPL_H_
 
 #include <list>
 #include <set>
 #include <string>
@@ skipping 525 matching lines @@
   bool PrepareTextureMailbox(
       cc::TextureMailbox* mailbox,
       scoped_ptr<cc::SingleReleaseCallback>* release_callback,
       bool use_shared_memory) override;
 
   // RenderFrameObserver
   void OnDestruct() override;
 
   // PluginInstanceThrottler::Observer
   void OnThrottleStateChange() override;
+  void OnHiddenForPlaceholder(bool hidden) override;
 
   void AddLatencyInfo(const std::vector<ui::LatencyInfo>& latency_info);
 
  private:
   friend class base::RefCounted<PepperPluginInstanceImpl>;
   friend class PpapiPluginInstanceTest;
   friend class PpapiUnittest;
 
   // Delete should be called by the WebPlugin before this destructor.
   ~PepperPluginInstanceImpl() override;
@@ skipping 375 matching lines @@
   // view change events.
   base::WeakPtrFactory<PepperPluginInstanceImpl> view_change_weak_ptr_factory_;
   base::WeakPtrFactory<PepperPluginInstanceImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PepperPluginInstanceImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_PLUGIN_INSTANCE_IMPL_H_