GitLab

Sets the height of the arrow button to match the bounds of the other
shelf buttons to place the tooltip at the same height.

Bug: 1043009
Change-Id: I7c83a825c41a5378eefc520023dcc25e6e25de64
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2033821Reviewed-by: Andrew Xu <andrewxu@chromium.org>
Reviewed-by: Manu Cornet <manucornet@chromium.org>
Commit-Queue: Ana Salazar <anasalazar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#737919}