GitLab

Move below unit tests to AppService folder, because they use
AppServiceAppModelBuilder for test:
CrostiniAppModelBuilderTest
ExtensionAppModelBuilderTest
InternalAppModelBuilderTest

BUG=1016159

Change-Id: I2aef91d4bb3b847a8861dca6b692bd0d92f0c4de
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1942897Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Nancy Wang <nancylingwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#720731}