Make window.open() IPCs be frame-based

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 e04fc32b4788b657b490fdf6ea613d3d33bed4d2..9f65e60eef8ec63bb6acc6f7023c84ff02e0a4d0 100644
--- a/content/common/frame_messages.h
+++ b/content/common/frame_messages.h
@@ -585,6 +585,16 @@ IPC_STRUCT_BEGIN(FrameHostMsg_ShowPopup_Params)
 IPC_STRUCT_END()
 #endif
 
+// Causes a window previously opened via RenderMessageFilter::CreateNewWindow to
+// be shown on the screen. This message is routed to the preexisting frame that
+// opened the window, and |pending_widget_routing_id| corresponds to the
+// widget routing id from the CreateNewWindow reply.
+IPC_MESSAGE_ROUTED4(FrameHostMsg_ShowCreatedWindow,
+                    int /* pending_widget_routing_id */,
+                    WindowOpenDisposition /* disposition */,
+                    gfx::Rect /* initial_rect */,
+                    bool /* opened_by_user_gesture */)
+
 #if BUILDFLAG(ENABLE_PLUGINS)
 IPC_STRUCT_TRAITS_BEGIN(content::PepperRendererInstanceData)
   IPC_STRUCT_TRAITS_MEMBER(render_process_id)