Protect mock with lock to fix flakiness, add two tests to presubmit

AppWindowTokenAnimationTests and DisplayContentTests are no longer
flaky. Removed the annotation respectively.

The fix of WrongTypeOfReturnValue flakiness works, as in
787b244dbb0a5b43e3b5b95dc1cf347ca8ae1400. Apply the fix to two more
cases.

Bug: 117117823
Bug: 124357362
Bug: 74078662
Bug: 123654474
Test: presubmit
Test: atest WindowStateTests
Test: atest TaskStackTests
Change-Id: I2f6a870cf921dd6a874839e080ae5fb324f36e6f
4 files changed