[DO NOT MERGE] Sync flicker from master to sc-v2

Flicker on master diverged form sc-v2, to make it easier to debug
flicker issues on sc-v2, push the current version of flicker into sc-v2

Test: atest FlickerTests WMShellFlickerTests
Bug: 188792659
Change-Id: I1c832bf32214b12ba4b708bccfc95cf259324844