The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c

commit fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c
Author: Takumi Fujimoto <takumif@chromium.org>
Date: Sat Mar 31 14:04:08 2018

Add a feature flag for Harmony/Views Cast dialog

Add the ViewsCastDialog feature, which replaces the WebUI Cast dialog
with a Views toolkit dialog when enabled. The feature flag is also made
accessible through chrome://flags.

The implementation for the feature will land in the future.

Bug:  825989 
Change-Id: Ib69a2a56362093d0e42e53b747ba0fdc9f0c5778
Reviewed-on: https://chromium-review.googlesource.com/982635
Commit-Queue: Takumi Fujimoto <takumif@chromium.org>
Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547385}
[modify] https://crrev.com/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c/chrome/browser/about_flags.cc
[modify] https://crrev.com/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c/chrome/browser/flag_descriptions.cc
[modify] https://crrev.com/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c/chrome/browser/flag_descriptions.h
[modify] https://crrev.com/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c/chrome/common/chrome_features.cc
[modify] https://crrev.com/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c/chrome/common/chrome_features.h
[modify] https://crrev.com/fb71e33c14f52c6d50b2f8cc78c8a8d34acfc91c/tools/metrics/histograms/enums.xml