Do not update time offset for time lapse recording after pause

For cases when StagefrightRecorder is used for recording
videos with a different capture and frame ratio (time lapse
or slow motion) with a surface source, recorded video
is incorrectly updated by a capture/recorded fps ratio.

To fix this, such factor will be used only with camera source.

Bug: 119070689
Test: timelapse/slowmotion and pause/resume with surface input

Change-Id: Id9df526324f3ead8117eb4571f9459beceea9fff