CTSVerifier additions for bubbles

1) Better tests around app settings & feature level
   settings. Notably ensures that the app settings page
   remains available when the feature is off & that the
   user is prompted to turn the feature on if they enable
   something on the apps page.
2) Tests for overflow existing and behavior around bubbles
   in the overflow.
3) Tests for important visuals in the expanded state (e.g.
   things that OEMs broke in R like the scrim, IME).
   And a test for the location of bubbles at the top &
   sides for portrait & landscape & enforcing min height.

Test: manual - install CTSVerifier, go through the tests
      for bubbles, make sure they all make sense and pass.
Bug: 182576750
Bug: 179938835
Bug: 178816777
Bug: 182934996
Change-Id: I574c45667ace804ebf801fb9b26faf933f03dc50