Trigger mediascan after a download is completed.

When a media item is inserted, media_type will be
automatically updated but some of the other media
attributes will only be updated after a media scan.

Bug: 138419471
Test: manual
Test: atest DownloadProviderTests
Test: atest cts/tests/app/src/android/app/cts/
Test: atest cts/tests/app/DownloadManagerLegacyTest/src/android/app/cts/
Test: atest cts/tests/app/DownloadManagerApi28Test/src/android/app/cts/
Change-Id: If8192b31fb7da37425480e7afa53dd1304533b76
(cherry picked from commit 90de12ad0c76fa9e231b3864c4afb8f312b53dda)
2 files changed