Add an option in the InCall UI to perform call recording

Change-Id: Icc86a0a7ae9d2493a837d02f321df7cb1387cded

Conflicts:
	res/values/cm_strings.xml
InCallUI: Fix NPE

Also properly add (and hide) button spacers.

Change-Id: I60a349f8e88ba81d90f286dff844825c222ddb86