Remote display framework support.

Any app can use the remote display APIs to mirror to another device...
This can be used to implement AirPlay, Chromecast, or even screen recording.

Change-Id: I6f45b393afb2f9d438d4aa548e8149946741c928

Conflicts:
	core/java/android/hardware/display/DisplayManager.java
	core/java/android/hardware/display/DisplayManagerGlobal.java
	core/java/android/hardware/display/IDisplayManager.aidl
	core/java/android/hardware/display/WifiDisplay.java
	services/java/com/android/server/display/DisplayManagerService.java