GitLab

Added tests for keyword button, pedal button, remove suggestion button,
multiple buttons for one suggestion (tab switch and keyword button).
Cleaned up tests.

Fixed a11y for remove suggestion button and buttons in dedicated row
(set role to be list box option and set correct accessible name).
Fixed selection event not being triggered for dedicated row buttons
(GetSecondaryButton wasn't returning buttons from dedicated row).
Fixed value changed event triggering extra time when switching selection
from button to button.

Bug: 1104264
Change-Id: I0c7a7a9cee0622cce2a24f6ea58c73a56ac996bc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2352826
Commit-Queue: Olesia Marukhno <olesiamarukhno@google.com>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#799723}