android: disable one ReturnToChromeTest

Disabling ReturnToChromeTest.testObserverModeTriggeredWithDelay, it has
been failing on a bot with KK Tablet since approximately the time when
it was introduced.

Bug: 955436

No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Change-Id: Ibcc0e8497019291de2d495aa7b8df93f6d73428f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1578747
Reviewed-by: Egor Pasko <pasko@chromium.org>
Commit-Queue: Egor Pasko <pasko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653163}
1 file changed