Move middle-click autoscroll to synthetic fling.

content/common/view_messages.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.
 
 // IPC messages for page rendering.
 // Multiply-included message file, hence no include guard.
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 661 matching lines @@
 
 // Sent to update part of the view.  In response to this message, the host
 // generates a ViewMsg_UpdateRect_ACK message.
 IPC_MESSAGE_ROUTED1(ViewHostMsg_UpdateRect,
                     ViewHostMsg_UpdateRect_Params)
 
 IPC_MESSAGE_ROUTED0(ViewHostMsg_Focus)
 
 IPC_MESSAGE_ROUTED1(ViewHostMsg_SetCursor, content::WebCursor)
 
+// Request a non-decelerating synthetic fling animation to be latched on the
+// scroller at the start point, and whose velocity can be changed over time by
+// sending multiple AutoscrollFling gestures.  Used for features like
+// middle-click autoscroll.
+IPC_MESSAGE_ROUTED1(ViewHostMsg_AutoscrollStart, gfx::PointF /* start */)
+IPC_MESSAGE_ROUTED1(ViewHostMsg_AutoscrollFling, gfx::Vector2dF /* velocity */)
+IPC_MESSAGE_ROUTED0(ViewHostMsg_AutoscrollEnd)
+
 // Get the list of proxies to use for |url|, as a semicolon delimited list
 // of "<TYPE> <HOST>:<PORT>" | "DIRECT".
 IPC_SYNC_MESSAGE_CONTROL1_2(ViewHostMsg_ResolveProxy,
                             GURL /* url */,
                             bool /* result */,
                             std::string /* proxy list */)
 
 // A renderer sends this to the browser process when it wants to create a
 // worker.  The browser will create the worker process if necessary, and
 // will return the route id on in the reply on success.  On error returns
@@ skipping 179 matching lines @@
                     int /* y */)
 
 #elif defined(OS_MACOSX)
 // Receives content of a web page as plain text.
 IPC_MESSAGE_ROUTED1(ViewMsg_GetRenderedTextCompleted, std::string)
 #endif
 
 // Adding a new message? Stick to the sort order above: first platform
 // independent ViewMsg, then ifdefs for platform specific ViewMsg, then platform
 // independent ViewHostMsg, then ifdefs for platform specific ViewHostMsg.