Pending CL: https://chromium-review.googlesource.com/c/chromium/src/+/704695

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d41f5acd5f1827c6dca149844c303363bf170a1e

commit d41f5acd5f1827c6dca149844c303363bf170a1e
Author: Becca Hughes <beccahughes@chromium.org>
Date: Thu Oct 12 20:17:05 2017

Media Controls: Collect the time to act as a metric

For the overflow icons experiment, collect the time to act on the
overflow menu as a histogram. The histogram uses 100x 1-second
buckets and will record up to 100 seconds.

BUG= 771929 
NOTRY=true  # win7_chromium_rel_ng issue tracked in 774136

Change-Id: I379b95eda4d091870ad071b093642c2dc0e59771
Reviewed-on: https://chromium-review.googlesource.com/704695
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Cr-Commit-Position: refs/heads/master@{#508435}
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.cpp
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/MediaControlsImpl.h
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/MediaControlsImplTest.cpp
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/elements/MediaControlInputElement.cpp
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/elements/MediaControlInputElement.h
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/elements/MediaControlOverflowMenuListElement.cpp
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/third_party/WebKit/Source/modules/media_controls/elements/MediaControlOverflowMenuListElement.h
[modify] https://crrev.com/d41f5acd5f1827c6dca149844c303363bf170a1e/tools/metrics/histograms/histograms.xml