GitLab

Collapse button use kUnifiedMenuExpandIcon now, remove the old one. And
update the function name from OnEnabledChanged to UpdateVectorIcon.

Bug: 1131543
Change-Id: I5d42a7941b07255da1ccc267bc5b44934dc4f492
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2486661
Commit-Queue: Min Chen <minch@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#819927}