Add profiling to track jank in ResourceDispatcherHostImpl::UpdateLoadInfoOnUIThread.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 977824c9a05b787b814e7a853d960748d64a8f37..8d8b76fefd5aba0844dadafe4553d8deef731fc3 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -11,6 +11,7 @@
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/process/process.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ -1052,6 +1053,11 @@ bool WebContentsImpl::IsBeingDestroyed() const {
 
 void WebContentsImpl::NotifyNavigationStateChanged(
     InvalidateTypes changed_flags) {
+  // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466285
+  // is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "466285 WebContentsImpl::NotifyNavigationStateChanged"));
   // Create and release the audio power save blocker depending on whether the
   // tab is actively producing audio or not.
   if ((changed_flags & INVALIDATE_TYPE_TAB) &&
@@ -4189,6 +4195,11 @@ void WebContentsImpl::LoadStateChanged(
     const net::LoadStateWithParam& load_state,
     uint64 upload_position,
     uint64 upload_size) {
+  // TODO(erikchen): Remove ScopedTracker below once http://crbug.com/466285
+  // is fixed.
+  tracked_objects::ScopedTracker tracking_profile1(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "466285 WebContentsImpl::LoadStateChanged::Start"));
   load_state_ = load_state;
   upload_position_ = upload_position;
   upload_size_ = upload_size;