Allow MimeHandlerViewGuest be embedded inside OOPIFs

components/guest_view/common/guest_view_messages.h

Index: components/guest_view/common/guest_view_messages.h
diff --git a/components/guest_view/common/guest_view_messages.h b/components/guest_view/common/guest_view_messages.h
index acec2c620371ecffc9473c0dcd1451cba2266d7e..d57864b543329c12829810e3b10d2df550093e7d 100644
--- a/components/guest_view/common/guest_view_messages.h
+++ b/components/guest_view/common/guest_view_messages.h
@@ -33,9 +33,10 @@ IPC_MESSAGE_CONTROL1(GuestViewMsg_GuestDetached,
 
 // Sent by the renderer to set initialization parameters of a Browser Plugin
 // that is identified by |element_instance_id|.
-IPC_MESSAGE_CONTROL3(GuestViewHostMsg_AttachGuest,
+IPC_MESSAGE_CONTROL4(GuestViewHostMsg_AttachGuest,
                      int /* element_instance_id */,
                      int /* guest_instance_id */,
+                     int /* embedder_routing_id */,
                      base::DictionaryValue /* attach_params */)
 
 // We have a RenderFrame with routing id of |embedder_local_frame_routing_id|.