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This CL adds e2e test to verify behavior of adaptive toolbar in grid
tab switcher. Situations that are tested are:
* Portrait and landscape +GTS +Duet
* Portrait and landscape +GTS -Duet
* Portrait and landscape -GTS +Duet

Bug: 1012014
Change-Id: Ib82f38a60f8f8649d6961a59463e743dbbe0d7b1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1938464
Commit-Queue: Yue Zhang <yuezhanggg@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Reviewed-by: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#721750}