Reject flings on seek bar

This should help reduce accidentials seek. A gesture that includes a
fling will be rejected. The progress will be returned to the place where
it was located at the start of the gesture.

Fixes: 155673905
Test: atest tests/src/com/android/systemui/media/SeekBarViewModelTest.kt
Test: manual - fling seek bar. It should bounce back.
Change-Id: Id0846d671c17d7362d45afec3e77676e764d96b3