Update from https://crrev.com/315085

cc/trees/single_thread_proxy.cc

Index: cc/trees/single_thread_proxy.cc
diff --git a/cc/trees/single_thread_proxy.cc b/cc/trees/single_thread_proxy.cc
index dc58d39a0911e9561feb942e27c0bd168e9a568d..f913c1f1a011994ba0baa9674946907a784e7e26 100644
--- a/cc/trees/single_thread_proxy.cc
+++ b/cc/trees/single_thread_proxy.cc
@@ -7,6 +7,7 @@
 #include "base/auto_reset.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/debug/benchmark_instrumentation.h"
+#include "cc/debug/devtools_instrumentation.h"
 #include "cc/output/context_provider.h"
 #include "cc/output/output_surface.h"
 #include "cc/quads/draw_quad.h"
@@ -204,6 +205,8 @@ void SingleThreadProxy::DoCommit() {
 
   commit_requested_ = false;
   layer_tree_host_->WillCommit();
+  devtools_instrumentation::ScopedCommitTrace commit_task(
+      layer_tree_host_->id());
 
   // Commit immediately.
   {