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This CL adds the following user actions for TabGroups UI:
  * GridTabSwitcher.UndoCloseTab
  * GridTabSwitcher.UndoCloseTabGroup
  * TabGridSheet.UndoCloseTab
  * TabStrip.UndoCloseTab

Bug: 950190
Change-Id: Ic456b9f118e185f62c3866492e77ade27b51f7aa
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1553090
Commit-Queue: Mei Liang <meiliang@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#649244}