Revert "[3/3] InCallUI: allow disabling non intrusive incall ui"

This reverts commit 2eb4c7a5fa21da93040aa734a00f48edd5d17fc3.
Revert "[1/2] InCall: Add a non-intrusive dialog for incoming calls"

This reverts commit bfa7a56f71f7a8adede0ffd3b54ea849e164eb6f.