The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/451b9a1abde5aaa5a40de7e2028d8f4284f317ac

commit 451b9a1abde5aaa5a40de7e2028d8f4284f317ac
Author: Takumi Fujimoto <takumif@chromium.org>
Date: Thu Aug 30 23:07:16 2018

[Harmony Cast Dialog] Add per-sink stop button

Before this CL, the user could click on the entire sink button to stop
casting. This CL makes just the stop button within the sink button
clickable.

The sink button and the stop button in it are given the same tag, so
CastDialogView that handles the clicks doesn't distinguish between the
two.

Icon size and padding are also adjusted to match the mocks. The icon
used in the sink button is tentative and will be replaced.

Screencap:
https://drive.google.com/open?id=1pT8U3712lotA8D-VaIwY-tROKIBuMvYB

Bug:  878194 
Change-Id: I42346bad4d40d9c119325e3dd245a61d5fd70397
Reviewed-on: https://chromium-review.googlesource.com/1192355
Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Commit-Queue: Takumi Fujimoto <takumif@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587828}
[modify] https://crrev.com/451b9a1abde5aaa5a40de7e2028d8f4284f317ac/chrome/browser/ui/views/media_router/cast_dialog_sink_button.cc
[modify] https://crrev.com/451b9a1abde5aaa5a40de7e2028d8f4284f317ac/chrome/browser/ui/views/media_router/cast_dialog_sink_button.h
[modify] https://crrev.com/451b9a1abde5aaa5a40de7e2028d8f4284f317ac/chrome/browser/ui/views/media_router/cast_dialog_sink_button_unittest.cc
[modify] https://crrev.com/451b9a1abde5aaa5a40de7e2028d8f4284f317ac/chrome/browser/ui/views/media_router/cast_dialog_view.cc