GitLab

Delete not used LabelTrayView. Also DEFAULT_VIEW_LABEL and
AddIconAndLabelForDefaultView that only used by this class.
Also delete AddIconAndLabels, which is not used any more either.

Bug: 982950
Change-Id: If1fd29d8273394ae0e38705c68ba7b53156a158c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1764271Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Min Chen <minch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690006}