Allow installd to chown/chmod app data files.

Addresses denials such as:
avc: denied { setattr } for comm="installd" name="com.android.calendar_preferences_no_backup.xml" dev="mmcblk0p28" ino=1499393 scontext=u:r:installd:s0 tcontext=u:object_r:app_data_file:s0 tclass=file                                        avc: denied { setattr } for comm="installd" name="calendar_alerts.xml" dev="mmcblk0p28" ino=1499463 scontext=u:r:installd:s0 tcontext=u:object_r:app_data_file:s0 tclass=file
avc: denied { setattr } for comm="installd" name="_has_set_default_values.xml" dev="mmcblk0p28" ino=1499428 scontext=u:r:installd:s0 tcontext=u:object_r:app_data_file:s0 tclass=file

Change-Id: I0622f1a9d2b10e28be2616f91edf33bc048b4ac7
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>