Clear controls and animations in temp arrays after using them

The arrays would be cleared while next time we use them, so they could
constantly occupy the memory.

This CL clears the temp arrays right after we use them. So they won't
occupy the memory while they are not being used.

Fix: 183684434
Test: Use Android Memory Profiler to check if there is
      InsetsAnimationControlImpl or WindowInsetsAnimation instances
      after GCing after playing insets animation in Launcher.
Change-Id: Iaae1e11d1c0cc1a9ac345beb3d7e8b596ea1b4ba