There are now three rules that guard intent filter priorities:
1) Only privileged applications will be granted a >0 priority
filter [previously, _all_ system applications could do this]
2) There are certain actions that are considered protected [eg
ACTION_VIEW, ACTION_SEND, ...] and even privileged applications
will NOT be granted a >0 priority filter. There is one, and
only one, exception for the SetupWizard.
3) Updates will NOT be granted a priority greater than the priority
defined on the system image.
Bug: 27450489
Change-Id: Ifcec4d7a59e684331399abc41eea1bd6876155a4
