Rename ButtonMediumStyle to AccentMediumStyle.

Change-Id: I8a9b22b7bee8aff0d75d050f18e0c0e7ff448ace
Reviewed-on: https://chromium-review.googlesource.com/c/1416145
Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#624180}
1 file changed