Enable PDF accessibility when RenderFrame's accessibility mode changes.

content/public/renderer/render_frame_observer.h

 // Copyright 2013 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_PUBLIC_RENDERER_RENDER_FRAME_OBSERVER_H_
 #define CONTENT_PUBLIC_RENDERER_RENDER_FRAME_OBSERVER_H_
 
 #include <stdint.h>
 
 #include "base/compiler_specific.h"
@@ skipping 104 matching lines @@
   virtual void DidChangePerformanceTiming() {}
 
   // Notification when the renderer uses a particular code path during a page
   // load. This is used for metrics collection.
   virtual void DidObserveLoadingBehavior(
       blink::WebLoadingBehaviorFlag behavior) {}
 
   // Called when the focused node has changed to |node|.
   virtual void FocusedNodeChanged(const blink::WebNode& node) {}
 
+  // Called when accessibility is enabled or disabled.
+  virtual void AccessibilityModeChanged() {}
+
   // IPC::Listener implementation.
   bool OnMessageReceived(const IPC::Message& message) override;
 
   // IPC::Sender implementation.
   bool Send(IPC::Message* message) override;
 
   RenderFrame* render_frame() const;
   int routing_id() const { return routing_id_; }
 
  protected:
@@ skipping 10 matching lines @@
   RenderFrame* render_frame_;
   // The routing ID of the associated RenderFrame.
   int routing_id_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderFrameObserver);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_RENDER_FRAME_OBSERVER_H_