Plumb refresh and render rates into shared timeline

* Make the overridden frame rate from the Scheduler public so that
SurfaceFlinger can access it for each uid.
* Add the display refresh rate on each display frame
* Add the application rendering rate on each SurfaceFrame created
* If there is no application rendering rate, then set it to the display
refresh rate.
* Plumb all those metrics into TimeStats.
* Change global metrics to increment for every SurfaceFrame instead of
every DisplayFrame, so that the rendering rate dimension can be
accurately captured.

Bug: 172937287
Test: builds, boots, timestats dump
Change-Id: Icfd4cecfdfa5d6c434661cab91c624eb08e8baea