framework/base: Add EdgeGesture service.

Based on code of PieService.

Change-Id: I053737e36340a5ec6814b21eb87575f9689c7e88

Conflicts:

	core/res/res/values/config.xml
	core/res/res/values/symbols.xml
PhoneWindowManager: add ability to use Pie service for system gestures.

Change-Id: Id4e2c0d82f771cd1c20e9196fb6db347494cca69