Fixes blurry border on suggestion chips, uses standard focus ring.

Removes some legacy code and unused overrides, removes chip mask
as it is no longer needed via |SetRoundedCornerRadius|

Changes suggestion chips to use focus painter to prepare for the future
implementation of themes.

Bug: 953559
Change-Id: I34373a2ba2c6ae84b4482b2cc8946a6624a33ba2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1580819
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Kevin Strohbehn <ginko@google.com>
Cr-Commit-Position: refs/heads/master@{#653745}
3 files changed