DO NOT MERGE: DropBoxTest needs PACKAGE_USAGE_STATS permission

b/78355661 adds PACKAGE_USAGE_STATS permission for getEntry API
in DropBoxManager. if this permission is not requested getEntry API
returns null

Bug: 147127741
Test: atest FrameworksServicesTests:com.android.server.DropBoxTest

Change-Id: Id84191a89fbb976c02d3dd3a84444b5e5df82eb1
Signed-off-by: Naga Venkata Durga Ashok Mutyala <quic_nmutya@quicinc.com>