We can now locate event log tag definitions in individual packages
(and java constants for the tag numbers get auto-generated), so move
all the tags used by the system server into the package.
Applications can now declare that they support small, normal, or
large screens. Resource selection can also be done based on these
sizes. By default, pre-Donut apps are false for small and large,
and Donut or later apps are assumed to support all sizes. In either
case they can use <supports-screens> in their manifest to declare
what they actually support.
