Populate preferred frame timeline always

`getLatestVsyncEventData` sometimes ends up with 0 length frame
timelines. When `generateFrameTimeline`, always populate with the
preferred timeline information from the vsync schedule.

Bug: 282110947
Test: atest EventThreadTest
Test: atest DisplayEventReceiverTest
Change-Id: I936d3b7095ce89ce3bd898f6b6a4f73145c27160
1 file changed