[1/2]Base: Stylus Gestures

PatchSet:
- start observer only on supported devices
- cleanup

Change-Id: I35f5b9128ffff4df87c160e27cf86624ed6333e7
Base: Toggle Stylus Pointer Icon

For devices with s-pen, this adds an option to disable
the mouse pointer when using s-pen

needs https://gerrit.slimroms.net/57

PatchSet:
- only observe if device supports it

Change-Id: Ic66390f8a9607cdaa2087f1fd8f502794592eb0f