Move non-Chrome ApplicationTestUtils to base/

These utilities are useful across Chrome, including within base/.

ApplicationStatus was avoided as it's not usable by WebView and doesn't
belong in base.

Bug: 1134178
Change-Id: I3913335667dc350b55a8242e0a3afb72a9a880b2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2519766


Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#824490}