Revert "Allow back to be pressed while in incoming call screen"

This reverts commit bd9ccd501ebd83508dfe52121e0f4827cc6e1fa3.

Bug: 18742942
Change-Id: I8016ddae8addb56b4d6350748628fec351e6531a
1 file changed
tree: 37978b6232a6c35dd586d00a6b951f0f4b3555b3
  1. InCallUI/