Clean up scan calls used for testing.

We've converged on explicit scanVolume() and scanFile() methods
which tests should be calling.  These are more robust than the
previous broadcast-based events, which could hang for a long time.

Bug: 127323913
Test: atest --test-mapping packages/apps/MediaProvider
Change-Id: I8ac13fa39252d1cd21b2df9a01caef313a0935a1
2 files changed