Set correct viewport size for an out of process iframe.

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/frame_param.h"
 #include "content/public/common/common_param_traits.h"
@@ skipping 101 matching lines @@
 // Sent in response to a FrameHostMsg_ContextMenu to let the renderer know that
 // the menu has been closed.
 IPC_MESSAGE_ROUTED1(FrameMsg_ContextMenuClosed,
                     content::CustomContextMenuContext /* custom_context */)
 
 // Executes custom context menu action that was provided from Blink.
 IPC_MESSAGE_ROUTED2(FrameMsg_CustomContextMenuAction,
                     content::CustomContextMenuContext /* custom_context */,
                     unsigned /* action */)
 
+// Instructs the frame to swap out for a cross-site transition, including
+// running the unload event handler. Expects a SwapOut_ACK message when
+// finished.
+IPC_MESSAGE_ROUTED0(FrameMsg_SwapOut)
+
 // -----------------------------------------------------------------------------
 // Messages sent from the renderer to the browser.
 
 // Sent by the renderer when a child frame is created in the renderer. The
 // |parent_frame_id| and |frame_id| are NOT routing ids. They are
 // renderer-allocated identifiers used for tracking a frame's creation.
 //
 // Each of these messages will have a corresponding FrameHostMsg_Detach message
 // sent when the frame is detached from the DOM.
 //
@@ skipping 85 matching lines @@
 // See FrameMsg_CompositorFrameSwapped
 IPC_MESSAGE_ROUTED1(FrameHostMsg_CompositorFrameSwappedACK,
                     FrameHostMsg_CompositorFrameSwappedACK_Params /* params */)
 
 // Indicates that the current frame has swapped out, after a SwapOut message.
 IPC_MESSAGE_ROUTED0(FrameHostMsg_SwapOut_ACK)
 
 IPC_MESSAGE_ROUTED1(FrameHostMsg_ReclaimCompositorResources,
                     FrameHostMsg_ReclaimCompositorResources_Params /* params */)
 
-// Instructs the frame to swap out for a cross-site transition, including
-// running the unload event handler. Expects a SwapOut_ACK message when
-// finished.
-IPC_MESSAGE_ROUTED0(FrameMsg_SwapOut)
-
 // Used to tell the parent that the user right clicked on an area of the
 // content area, and a context menu should be shown for it. The params
 // object contains information about the node(s) that were selected when the
 // user right clicked.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_ContextMenu, content::ContextMenuParams)
+
+// Initial drawing parameters for a child frame that has been swapped out to
+// another process.
+IPC_MESSAGE_ROUTED2(FrameHostMsg_InitializeChildFrame,
+                    gfx::Rect /* frame_rect */,
+                    float /* scale_factor */)