Correct the state when prevent ringing page is launched.

When prevent ringing page is opened, the switch gets checked and is set
to vibrate in default. Make it set to a correct state based on the value
stored in Settings.Secure.VOLUME_HUSH_GESTURE.

Fixes: 129728579
Test: robotests
Change-Id: I1063db9fe79800eb2e400810e2414ee650076ea0