all: fix db memory leak

Fix an issue where the database instances would leak memory due to an
incorrect context use.

app/src/main/java/org/oxycblt/auxio/music/extractor/CacheExtractor.kt

@@ -187,7 +187,9 @@ private abstract class CacheDatabase : RoomDatabase() {
             synchronized(this) {
                 val newInstance =
                     Room.databaseBuilder(
-                            context, CacheDatabase::class.java, "auxio_metadata_cache.db")
+                            context.applicationContext,
+                            CacheDatabase::class.java,
+                            "auxio_metadata_cache.db")
                         .fallbackToDestructiveMigration()
                         .fallbackToDestructiveMigrationFrom(0)
                         .fallbackToDestructiveMigrationOnDowngrade()

app/src/main/java/org/oxycblt/auxio/playback/persist/PersistenceDatabase.kt

@@ -69,7 +69,7 @@ abstract class PersistenceDatabase : RoomDatabase() {
             synchronized(this) {
                 val newInstance =
                     Room.databaseBuilder(
-                            context,
+                            context.applicationContext,
                             PersistenceDatabase::class.java,
                             "auxio_playback_persistence.db")
                         .fallbackToDestructiveMigration()

app/src/main/java/org/oxycblt/auxio/playback/state/PlaybackStateManager.kt

@@ -280,6 +280,7 @@ interface PlaybackStateManager {
          */
         fun get(): PlaybackStateManager {
             val currentInstance = INSTANCE
+            logD(currentInstance)
 
             if (currentInstance != null) {
                 return currentInstance
@@ -553,6 +554,7 @@ private class RealPlaybackStateManager : PlaybackStateManager {
             // Internal player may have reloaded the media item, re-seek to the previous position
             seekTo(savedState.positionMs)
         }
+        isInitialized = true
     }
 
     // --- CALLBACKS ---