Changing MenuRunner::RunMenuAt to take in a MenuButtonController.

This is needed so Buttons can be not a subclass of MenuButton but still
install a MenuButtonController for the same behavior.

Bug: 901183, 819854
Change-Id: Iccd82dab68ba243f86a8784916332030a295b9ff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1503349
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Michael Wasserman <msw@chromium.org>
Reviewed-by: Taylor Bergquist <tbergquist@chromium.org>
Commit-Queue: Charlene Yan <cyan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#652633}
53 files changed