Frameworks: Fix do not show snappoints if triggermask disables edge

as the title says do not show on lockscreen or notification
drawer the snappoints on the disabled edges. Pass
trigger slots and mask trough and take into account

PatchSet 2:
- some refactoring

Change-Id: I0413ffe86169c5d1cb906598d6006bbf1463770b
Merge branch 'cm-10.1' of git://github.com/CyanogenMod/android_frameworks_base into cm-10.1-n7