GitLab

If the method is called a second time, instead make a window priority
request.

Bug: internal 160358649
Test: on device
Change-Id: I6b38cafb3198a607136e54542f65c6f4df8b163b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2293419Reviewed-by: Luke Halliwell (slow) <halliwell@chromium.org>
Commit-Queue: Cicy Tan <shiyun@google.com>
Cr-Commit-Position: refs/heads/master@{#787432}