Change foregroundServiceType from enum to flags

1. Now the value of manifest attribute foregroundServiceType can
be multiple flags ORed together.
2. Add a overloaded version of Service.startForeground() with an
additional parameter foregroundServiceType. The flags in parameter
foregroundServiceType must be a subset of flags specified in manifest
attribute foregroundServiceType, otherwise a IllegalArgumentException is
thrown.
3. Add a field foregroundServiceType in ServiceRecord, it is the types
that have been started on this foreground sevice.

Bug: 111453223
Test: atest frameworks/base/tests/FrameworkPerf

Change-Id: I7eb68f696e6bf75720fe9c9388a6c23a529677f7