added: MediaItemTag for ManagedMediaSources.
added: silent track for FailedMediaSource.
added: keyframe fast forward at initial playback buffer.
added: error notification on silently skipped streams.
* re-work finished mission database
* re-work DownloadMission and bump it Serializable version
* keep the classic Java IO API
* SAF Tree API support on Android Lollipop or higher
* add wrapper for SAF stream opening
* implement Closeable in SharpStream to replace the dispose() method
* do required changes for this API:
** remove any file creation logic from DownloadInitializer
** make PostProcessing Serializable and reduce the number of iterations
** update all strings.xml files
** storage helpers: StoredDirectoryHelper & StoredFileHelper
** best effort to handle any kind of SAF errors/exceptions
-Updated MediaSource contracts in ManagedMediaSource.
-Changed PlaceholderMediaSource and FailedMediaSource to use built-in BaseMediaSource implementation.
-Changed deprecated DynamicConcatenatingMediaSource to ConcatenatingMediaSource.
-Removed manual playlist media source disposal in favor of player built-in disposal.
-Changed main video player to always self-destruct on stop.
-Extracted main video player lifecycle states into separate data class.
-Fixed play queue in full repeat mode does not load first item after expiring.
-Refactored playlist manipulations out from media source manager.
-Fixed potential ArrayOutOfBound exception when checking if player window is live.
-Fixed service player play queue potentially not refreshing when current play queue is replaced.
-Fixed livestream not seeking to live when started from play queue.
-Fixed media source manager synchronization to only occur after timeline change has completed.
-Fixed auto queue not working when last item is replayed after the auto-queued item is removed.
-Updated ExoPlayer to 2.7.1.
-Added button to wipe metadata cache.
-Added more paddings on player buttons.
-Added new animations to main player secondary controls and play queue expand/collapse.
-Refactored play queue item touch callback for use in all players.
-Improved MediaSourceManager to better handle expired stream reloading.
-[#1186] Changed live sync button text to "LIVE".
-Removed MediaSourceManager loader coupling on main players.
-Moved service dependent expiry resolution to ServiceHelper.
-[#1186] Fixed livestream timeline updates causing negative time position.
-[#1186] Fixed livestream not starting from live-edge.
-Fixed main player system UI not retracting on playback start.
-Improved player sync calls to recognize different metadata updates.
-Changed MediaSourceManager to synchronize only after timeline changes and reenabled multiple sync calls to player.
-Renamed listener and synchronization methods related to MediaSourceManager.
-Added nonnull and final constraints to variables in MediaSourceManager.
-Added nonnull and final constraints on context related objects in BasePlayer.
-Fixed Hls livestreams crashing player when behind live window for too long.
-Fixed cache miss when InfoCache key mismatch between StreamInfo and StreamInfoItem.
-Modified LoadController to allow fast playback start and increased buffer zigzag window.
-Removed unnecessary loading on timeline changes.
-Changed select message in MediaSourceManager to cause immediate load.
-Reduced default expiration time in MediaSourceManager.
-Fixed main video player not showing end time on audio-only streams.
-Fixed live stream has player view disabled after transitioning from audio stream.
-Fixed inconsistent progress bar height between live and non-live video on main player.
-Fixed play queue playlist desynchronization caused by media source manager window loading expansion on sublist prior to current item.
-Fixed failed media source not treated as ready for playback.
-Added sync buttons on live streams to allow seeking to live edge.
-Added custom cache key for extractor sources to allow more persistent reuse.
-Refactored player data source factories into own class and separating live and non-live data sources.
-Extracted expiration time in media source manager.
-Re-enabled long click on live stream info items.
-Fixed dash source building to use mpd instead of extractor.
-Fixed live media sources failing when using cached data source by introducing
cacheless data sources.
-Added custom track selector to circumvent ExoPlayer's language normalization NPE.
-Updated Extractor to correctly load live streams.
-Removed deprecated deferred media source and media source manager.
-Removed Livestream exceptions.
-Added drag reorder speed clamping to play queue list.
-Fixed service player activity memory leak.
-Fixed media source manager sync disposable fallthrough causing NPE.
-Fixed thread bouncing during play queue item async stream resolution.
-Updated ExoPlayer to 2.6.0.
-Added play queue dropdown to playlist info items.
-Added Channel Play Queue.
-Renamed External Play Queue to Playlist Play Queue.
-Modified Playlist Play Queue to allow loading from initial state.
-Added selected item bullet.
-Modified play queue panel darker on main video player.
-Fixed color issue on play queue panel on light-themed main video player.
-Fixed hold-to-enqueue tooltip flashing when clicked on earlier sdk versions.
-Fixed queue item removal causing metadata for currently playing to refresh.