Bug 949358 - Orientation management for callscreen + lockscreen + active app

Conflicts:
	apps/system/js/orientation_manager.js
	apps/system/test/unit/orientation_manager_test.js
Merge pull request #15754 from alivedise/bugzilla/949358_v1.3/callscreen-orientation

Bug 949358 - Orientation management for callscreen + lockscreen + active...r=timdream, a=1.3+