Handle SQLiteDatabaseLockedException in CachedContentIndex

[balachandarlinks]

SQLiteException is not caught and converted to IOException when trying to access databaseProvider.getReadableDatabase(). Hence exoplayer is not handling this cache related exception and crashing. Similar exception is properly handled here.

Stacktrace:

android.database.sqlite.SQLiteDatabaseLockedException: database is locked (code 5)
	at android.database.sqlite.SQLiteConnection.nativeExecuteForLong()(SQLiteConnection.java:-2)
	at android.database.sqlite.SQLiteConnection.executeForLong()(SQLiteConnection.java:598)
	at android.database.sqlite.SQLiteSession.executeForLong()(SQLiteSession.java:652)
	at android.database.sqlite.SQLiteStatement.simpleQueryForLong()(SQLiteStatement.java:107)
	at android.database.DatabaseUtils.longForQuery()(DatabaseUtils.java:825)
	at android.database.DatabaseUtils.longForQuery()(DatabaseUtils.java:813)
	at android.database.sqlite.SQLiteDatabase.getVersion()(SQLiteDatabase.java:864)
	at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked()(SQLiteOpenHelper.java:241)
	at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase()(SQLiteOpenHelper.java:187)
	at com.google.android.exoplayer2.upstream.cache.CachedContentIndex$DatabaseStorage.exists()(CachedContentIndex.java:2)
	at com.google.android.exoplayer2.upstream.cache.CachedContentIndex.initialize()(CachedContentIndex.java:4)
	at com.google.android.exoplayer2.upstream.cache.SimpleCache.initialize()(SimpleCache.java:13)
	at com.google.android.exoplayer2.upstream.cache.SimpleCache.access$000()(SimpleCache.java:1)
	at com.google.android.exoplayer2.upstream.cache.SimpleCache$1.run()(SimpleCache.java:3)

This particular crash happens a lot in firetv specifically incomparison to Android tv and mobile.