Make rendering timeouts work even if paint data received early

content/common/view_messages.h

Index: content/common/view_messages.h
diff --git a/content/common/view_messages.h b/content/common/view_messages.h
index be4dd59d64627292ea984d7431448a6292c65b29..6cc815553d8d96f787fe3336ae3d61cd8f11ba5a 100644
--- a/content/common/view_messages.h
+++ b/content/common/view_messages.h
@@ -1333,6 +1333,12 @@ IPC_MESSAGE_ROUTED1(ViewHostMsg_MoveValidationMessage,
 // after the frame widget has painted something.
 IPC_MESSAGE_ROUTED0(ViewHostMsg_DidFirstVisuallyNonEmptyPaint)
 
+// Send after a paint happens after any page commit, including a blank one.
+// TODO(kenrb): This, and all ViewHostMsg_* messages that actually pertain to
+// RenderWidget(Host), should be renamed to WidgetHostMsg_*.
+// See https://crbug.com/537793.
+IPC_MESSAGE_ROUTED0(ViewHostMsg_DidFirstPaintAfterLoad)
+
 #if defined(OS_ANDROID)
 // Response to ViewMsg_FindMatchRects.
 //