Allow post-flash device setup to be skipped.

When flashing a signed build, post-flash device setup will cause
a DeviceNotAvailableException since the device will be flashed
with USB debugging off. Skipping these steps is necessary to
prevent a test failure being reported.

Bug: 25154366
Change-Id: Ia2608bc35a1f9da871955d355b55cba4c0d48d99
1 file changed