Fix activity config tests in ActivityThreadTest

If the activity doesn't declare to handle the corresponding config
change. The Activity#onConfigurationChanged won't be called.

Also add timeout to avoid test hangs.

Bug: 169550676
Test: testHandleActivityConfigurationChanged_ApplyNewConfigurations
 testHandleActivityConfigurationChanged_OnlyAppliesNewestConfiguration
Change-Id: I65bc363695ed475d89e6b6828a97c4fed460470a