This adds in the ability for Chrome to generate windows with snapshots of all...

chrome/common/render_messages_internal.h

 // Copyright (c) 2010 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.
 
 // This header is meant to be included in multiple passes, hence no traditional
 // header guard.
 // See ipc_message_macros.h for explanation of the macros and passes.
 
 #include <map>
 #include <string>
@@ skipping 123 matching lines @@
   IPC_MESSAGE_ROUTED2(ViewMsg_PrintingDone,
                       int /* document_cookie */,
                       bool /* success */)
 
   // Tells the renderer to dump as much memory as it can, perhaps because we
   // have memory pressure or the renderer is (or will be) paged out.  This
   // should only result in purging objects we can recalculate, e.g. caches or
   // JS garbage, not in purging irreplaceable objects.
   IPC_MESSAGE_CONTROL0(ViewMsg_PurgeMemory)
 
+  // Sent to render the view into the supplied transport DIB, scale it
+  // by the appropriate scale to make it fit the given size, and
+  // return it.  In response to this message, the host generates a
+  // ViewHostMsg_PaintAtSize_ACK message.
+  IPC_MESSAGE_ROUTED2(ViewMsg_PaintAtSize,
+                      TransportDIB::Handle /* dib_handle */,
+                      gfx::Size /* size */)
+
   // Tells the render view that a ViewHostMsg_UpdateRect message was processed.
   // This signals the render view that it can send another UpdateRect message.
   IPC_MESSAGE_ROUTED0(ViewMsg_UpdateRect_ACK)
 
   // Replies to creating and updating videos.
   IPC_MESSAGE_ROUTED1(ViewMsg_CreateVideo_ACK,
                       int32 /* video_id */)
   IPC_MESSAGE_ROUTED1(ViewMsg_UpdateVideo_ACK,
                       int32 /* video_id */)
 
@@ skipping 920 matching lines @@
 
   // Sent when the renderer fails a provisional load with an error.
   IPC_MESSAGE_ROUTED4(ViewHostMsg_DidFailProvisionalLoadWithError,
                       bool /* true if it is the main frame */,
                       int /* error_code */,
                       GURL /* url */,
                       bool /* true if the failure is the result of
                               navigating to a POST again and we're going to
                               show the POST interstitial */ )
 
+  // Tells the render view that a ViewHostMsg_PaintAtSize message was
+  // processed, and the DIB is ready for use.
+  IPC_MESSAGE_ROUTED2(ViewHostMsg_PaintAtSize_ACK,
+                      TransportDIB::Handle /* dib_handle */,
+                      gfx::Size /* size */)
+
   // 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)
 
   // Sent to create, update and destroy video layers.
   IPC_MESSAGE_ROUTED1(ViewHostMsg_CreateVideo,
                       gfx::Size /* size */)
   IPC_MESSAGE_ROUTED2(ViewHostMsg_UpdateVideo,
                       TransportDIB::Id /* bitmap */,
@@ skipping 1207 matching lines @@
                        int /* render_view_id */,
                        int /* bridge_id */)
 
   // The |render_view_id| and |bridge_id| requests Geolocation service to
   // resume.
   IPC_MESSAGE_CONTROL2(ViewHostMsg_Geolocation_Resume,
                        int /* render_view_id */,
                        int /* bridge_id */)
 
 IPC_END_MESSAGES(ViewHost)