The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6e510ddd1c70af1adefaf1ccc5ee42286dcd0ac3

commit 6e510ddd1c70af1adefaf1ccc5ee42286dcd0ac3
Author: ryansturm <ryansturm@chromium.org>
Date: Wed Mar 08 18:53:28 2017

TabRestore page load metrics does not track app background UMA properly

When the app enters the background only *uncommitted* page loads are
tracked, but only committed page loads should be tracked.

BUG= 699593 

Review-Url: https://codereview.chromium.org/2734363002
Cr-Commit-Position: refs/heads/master@{#455505}

[modify] https://crrev.com/6e510ddd1c70af1adefaf1ccc5ee42286dcd0ac3/chrome/browser/page_load_metrics/observers/page_load_metrics_observer_test_harness.cc
[modify] https://crrev.com/6e510ddd1c70af1adefaf1ccc5ee42286dcd0ac3/chrome/browser/page_load_metrics/observers/page_load_metrics_observer_test_harness.h
[modify] https://crrev.com/6e510ddd1c70af1adefaf1ccc5ee42286dcd0ac3/chrome/browser/page_load_metrics/observers/tab_restore_page_load_metrics_observer.cc
[modify] https://crrev.com/6e510ddd1c70af1adefaf1ccc5ee42286dcd0ac3/chrome/browser/page_load_metrics/observers/tab_restore_page_load_metrics_observer_unittest.cc