Added reasons for invisibility of a layer.

Test: Create an SFTrace that opens an app, then closes. Then test the
wide variety of layers created by this file.

Change-Id: Idd198cc6507c67a03f38cf3e34d737d319295c16
Merged-In: Idd198cc6507c67a03f38cf3e34d737d319295c16
1 file changed