Fix missing enable of USB test button upon peripheral plug in.

Bug: 358134112
Test: Run test, plug in USB headset adapter. Notice button is enabled.
Flag: TEST_ONLY
Change-Id: I0c6340e79b3fcf70feadfd84e926bb6d8e60f673
Merged-In: I0c6340e79b3fcf70feadfd84e926bb6d8e60f673
(cherry picked from commit 6f00adbbb367f1cfab59e2d2f739ea07a8c82f70)
1 file changed