Pausing videos do not always work about react-native-video

[isair]

setPaused seems to be called correctly with the right values. When setPaused is called with paused as true in my app, the progress update timer is stopped properly but player is not being paused. So it is definitely a threading issue. Will fix this.

Since all the property setters seem to be called asynchronously we should check them all and make sure what needs to be on the main thread stays on the main thread. I'll check and open another issue if necessary.

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From Apple's documentations:

AVPlayer serializes notifications of changes that occur dynamically during playback on a dispatch queue. By default, this queue is the main queue (see dispatch_get_main_queue). To ensure safe access to a player’s nonatomic properties while dynamic changes in playback state may be reported, you must serialize access with the receiver’s notification queue. In the common case, such serialization is naturally achieved by invoking AVPlayer’s various methods on the main thread or queue.