Revert "[2/3] Telephony: allow disabling non intrusive incall ui"

This reverts commit 50c4a241536de5b6858c56f38d258f932b7738d5.

Conflicts:
	res/values/custom_strings.xml
	src/com/android/phone/CallFeaturesSetting.java
Telephony: Heads up meets SlimKat....SlimKat meets Google IO [3/4]
Add heads up setting for the native integration in dialer

Enabled by default

PS
- derp

PS
update commit message header

Change-Id: I0a540f2dc2667d572797a68c07b6eb471653ec16

Conflicts:
	res/values/cr_strings.xml
	res/xml/call_feature_setting.xml
	src/com/android/phone/CallFeaturesSetting.java