[WebView] Remove onFailure from VisualStateCallback.

content/common/frame_messages.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.
 
 // IPC messages for interacting with frames.
 // Multiply-included message file, hence no include guard.
 
 #include "content/common/content_export.h"
 #include "content/common/content_param_traits.h"
 #include "content/common/frame_message_enums.h"
@@ skipping 824 matching lines @@
 // Tells the browser to perform a navigation.
 IPC_MESSAGE_ROUTED3(FrameHostMsg_BeginNavigation,
                     content::CommonNavigationParams,
                     content::BeginNavigationParams,
                     scoped_refptr<content::ResourceRequestBody>)
 
 // Sent once a paint happens after the first non empty layout. In other words
 // after the frame has painted something.
 IPC_MESSAGE_ROUTED0(FrameHostMsg_DidFirstVisuallyNonEmptyPaint)
 
+// Sent prior to delivering visual state messages, in order to
+// transport swap success/failure status.

[boliu, 2015/03/02 18:43:58]

Err, this is not it.

+IPC_MESSAGE_ROUTED2(FrameHostMsg_VisualStateSwapInfo,
+                    int /* source_frame_number */,
+                    bool /* swap_success */)
+
 // Sent as a response to FrameMsg_VisualStateRequest.
 // The message is delivered using RenderWidget::QueueMessage.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_VisualStateResponse, uint64 /* id */)
 
 // Puts the browser into "tab fullscreen" mode for the sending renderer.
 // See the comment in chrome/browser/ui/browser.h for more details.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_ToggleFullscreen, bool /* enter_fullscreen */)
 
 // Messages to signal the presence or absence of BeforeUnload or Unload handlers
 // for a frame. |present| is true if there is at least one of the handlers for
 // the frame.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_BeforeUnloadHandlersPresent,
                     bool /* present */)
 IPC_MESSAGE_ROUTED1(FrameHostMsg_UnloadHandlersPresent,
                     bool /* present */)
 
 // Dispatch a load event for this frame in the iframe element of an
 // out-of-process parent frame.
 IPC_MESSAGE_ROUTED0(FrameHostMsg_DispatchLoad)
 
 #if defined(OS_MACOSX) || defined(OS_ANDROID)
 
 // Message to show/hide a popup menu using native controls.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_ShowPopup,
                     FrameHostMsg_ShowPopup_Params)
 IPC_MESSAGE_ROUTED0(FrameHostMsg_HidePopup)
 
 #endif