Avoid divide-by-zero crashes by resetting render tracking

If content time does not advance forward, a divide-by-zero error can
occur unless the render quality tracking is reset. This is because the
delta between two content times will be zero, and the frame rate
computation will divide by this value.

Also, add additional counter-based metrics for when content time jumps forward, moves backwards, or stays stagnant.

Bug: 362547322
Test: atest DecoderRenderTest
Test: atest VideoRenderQualityTracker_test
Flag: EXEMPT bugfix
Change-Id: I5690ba49299701b74205bfdff994243bcdf4d433