Don't include audio items from ejected volume in the playlist

When app queries for audio files from playlist, we should only include
audio files of volumes that are attached. Previously, we included audio
files from all volumes, including the audio files from recently ejected
volumes. When app tries to read these files, this will resullt in an
error as file doesn't exist.

Changed query method to include only attached volume while querying for
audio files from playlists.

Added tests to verify the same.

Bug: 176199779
Test: atest
com.android.providers.media.client.ClientPlaylistTest#testEjectedVolume

Change-Id: Ibb2d5cb4e7bcecbc316ead53fdca9666e2a84000
Merged-In: Ibb2d5cb4e7bcecbc316ead53fdca9666e2a84000
(cherry picked from commit 750471dc98374bcf9a6de49eefa881e641648a4a)
4 files changed