Revert "fb: do not block home button if incoming call is a background call"

This reverts commit c435b290e740ab347a726abc5521d6901883d22b.

Conflicts:
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java
Revert "PhoneWindowManager: add ability to use EdgeGestureService for system gestures."

This reverts commit 1700c936e32bc1ab8c60ae8c67319570b969f6ce.

Conflicts:
	core/java/android/provider/Settings.java
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java