Revert "SurfaceFlinger: refresh rate calculation when no timestamps"

This reverts commit 38601a9beb0d4e849c8fb76733614a7ead777a69.

Reason for revert: Different fix was applied to b/155710271

Change-Id: Icfa0774f1cf412aa3d7122b0bc7046cf8a0b1077
Bug: 155710271
2 files changed