SF: add render frame rate dimension to RefreshRateSelector

RefreshRateSelector will now select the render frame rate in addition
to the display refresh rate. This will allow SF (in follow up CL)
to schedule frames based on the render frame rate instead of being
tied to the display refresh rate. The render frame rate is a divisor of
the display refresh rate.

Bug: 257071863
Test: atest libsurfaceflinger_unittest
Change-Id: Id6aaa389b431514fc06190d88d16eb9fcf0ba348
9 files changed