am 34656acb: Merge changes Ie7745ed2,I43d47589,Ie04279e2,I8426ace8,Id1195405, ... into lmp-docs

* commit '34656acb8fdb1473aec8bd437cd0644431a1e43f':
  Remove compile-sdk constraints from ImmersiveMode sample
  Remove compile-sdk constraints from BasicImmersiveMode sample
  Remove compile-sdk constraints from AdvancedImmersiveMode sample
  Remove compile-sdk constraints from BasicTransition sample
  CustomChoiceList: Increment min-sdk to 4
  ActivitySceneTransitionBasic: Update method calls for compatibility with API 21