Enable PDF accessibility when RenderFrame's accessibility mode changes.

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 <stddef.h>
 #include <stdint.h>
 
@@ skipping 534 matching lines @@
   // the given module.
   bool IsValidInstanceOf(PluginModule* module);
 
   // cc::TextureLayerClient implementation.
   bool PrepareTextureMailbox(
       cc::TextureMailbox* mailbox,
       std::unique_ptr<cc::SingleReleaseCallback>* release_callback,
       bool use_shared_memory) override;
 
   // RenderFrameObserver
+  void AccessibilityModeChanged() override;
   void OnDestruct() override;
 
   // PluginInstanceThrottler::Observer
   void OnThrottleStateChange() override;
   void OnHiddenForPlaceholder(bool hidden) override;
 
   PepperAudioController& audio_controller() {
     return *audio_controller_;
   }
 
@@ skipping 427 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_