SurfaceFlinger: keep layer history for inactive layers

The current implementation of layer history discards all the history
if a layer is considered inactive. This leads to an issue in the scenario
that a layer is posting infrequent updates so slow, that by the time we
get the next buffer, the layer is considered inactive, and we bump the
refresh rate to Max, instead of detecting that layer as infrequent.

As a fix, we keep around the layer history even if it is inactive.
To avoid cases where detect animations too late, we clear the history
on touch event.

Bug: 156654519
Test: add a new unit test that simulates the buffer pattern
of a Netflix playback

Change-Id: Ie076891806d74dde814fbbb3b1a73c38e0b2ae34