Changed all output file names (not paths) to follow the pattern that
any qualifier (e.g. trick play) will be join the current name using '-'
but will use '_' within itself (e.g. trick_play_1).
Change-Id: Ib0247bf1ca6d94815fedaaf73d3a400d31c20c40
Prefer timestamps from Video AdaptationSets if available - this avoids
possible video playback jitters due to gaps.
presentationTimeOffset is not applied to the first period as it may in
negative dts which Chrome does not like: https://crbug.com/398141.
It is safe to apply to subsequent periods as the actual offset applied
takes Period@start into consideration:
offset = Period@start - presentationTimeOffset
The result timestamp with offset applied is close to Period@start, so
it is unlikely to result in a negative dts value.
Closes b/73899306.
Change-Id: If8361f5469610093b3aac6675754536ad7e83c4c