Migrate accessibility from RenderView to RenderFrame.

content/common/frame_messages.h

Index: content/common/frame_messages.h
diff --git a/content/common/frame_messages.h b/content/common/frame_messages.h
index 6dbe9302c03da24f1c5ea42737103c232c034252..06eb8ebc05c05a9b4d4ee58e881408542d6a9de0 100644
--- a/content/common/frame_messages.h
+++ b/content/common/frame_messages.h
@@ -24,6 +24,9 @@
 
 #define IPC_MESSAGE_START FrameMsgStart
 
+IPC_ENUM_TRAITS_MIN_MAX_VALUE(AccessibilityMode,
+                              AccessibilityModeOff,
+                              AccessibilityModeComplete)
 IPC_ENUM_TRAITS_MIN_MAX_VALUE(content::JavaScriptMessageType,
                               content::JAVASCRIPT_MESSAGE_TYPE_ALERT,
                               content::JAVASCRIPT_MESSAGE_TYPE_PROMPT)
@@ -353,6 +356,10 @@ IPC_MESSAGE_ROUTED2(FrameMsg_DidChooseColorResponse, unsigned, SkColor)
 // Notifies the color chooser client that the color chooser has ended.
 IPC_MESSAGE_ROUTED1(FrameMsg_DidEndColorChooser, unsigned)
 
+// Change the accessibility mode in the renderer process.
+IPC_MESSAGE_ROUTED1(FrameMsg_SetAccessibilityMode,
+                    AccessibilityMode)
+
 // -----------------------------------------------------------------------------
 // Messages sent from the renderer to the browser.