Set correct viewport size for an out of process iframe.

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 625b0e09d0e33fa01ddd0bf33896eb07600257fb..019db0d7316660134cd39c0ff2d3a40a8e1480cc 100644
--- a/content/common/frame_messages.h
+++ b/content/common/frame_messages.h
@@ -119,6 +119,11 @@ 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.
 
@@ -224,13 +229,14 @@ 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 */)