Notifying the Out of Process Renderer about Visibility Change of a Remote Frame

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 ada844fa3a4b5c80804d9b559ac3ac55e52e93de..3174977db15ec5c0e574c7caed0eff1e2563caef 100644
--- a/content/common/frame_messages.h
+++ b/content/common/frame_messages.h
@@ -1043,6 +1043,10 @@ IPC_MESSAGE_ROUTED1(FrameHostMsg_ForwardInputEvent,
 // position of a child's ancestor has changed).
 IPC_MESSAGE_ROUTED1(FrameHostMsg_FrameRectChanged, gfx::Rect /* frame_rect */)
 
+// Informs the child that the frame has changed visibility. This message will
+// be then forwarded to the guest WebContents.
+IPC_MESSAGE_ROUTED1(FrameHostMsg_VisibilityChanged, bool /* visible */)
+
 // 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