WebApp: Add ordering unit test for InstallOrUpdateWebAppFromSync.

Let's test FIFO queue more properly.

Bug: 901226
Change-Id: I431bb427a74aa713b23f6cbdf77d8d20f0c52373
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1611430
Commit-Queue: Alexey Baskakov <loyso@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Cr-Commit-Position: refs/heads/master@{#660270}
4 files changed