SurfaceFlinger: use queueTime as well when calculating refresh rate

When calculating refresh rate, we want to make sure that the refresh
rate of a layer is "stable", meaning that the average we calculated
is correct for all the samples we have. If the app stops frame
production and then resumes we don't want to calculate the refresh
rate average across a different group of frames. This change enhances
the detection of when the app stops to produce a frame by looking at
the queue time of a frame if this frame doesn't have a timestamp.

Bug: 155710271
Test: Start an animation not driven by touch
Change-Id: Icef63a1ba86c1ad063592717115addd700e22cad