Notify DevTools when updating frame in RenderWidget

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index 6c092082f0e9fa50dd84fa157e0cb603cbda0164..f5d3f10b05df34c920991d2aadb011717384b629 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -829,6 +829,7 @@ void RenderWidget::DoDeferredUpdate() {
 
   // Tracking of frame rate jitter
   base::TimeTicks frame_begin_ticks = base::TimeTicks::Now();
+  webwidget_->instrumentBeginFrame();
   AnimateIfNeeded();
 
   // Layout may generate more invalidation.  It may also enable the
@@ -846,6 +847,7 @@ void RenderWidget::DoDeferredUpdate() {
   // animations running layout as these may generate further invalidations.
   if (!paint_aggregator_.HasPendingUpdate()) {
     TRACE_EVENT0("renderer", "EarlyOut_NoPendingUpdate");
+    webwidget_->instrumentCancelFrame();
     return;
   }