iOS fixes

[cguino]

#3166 Memory leaks
#3085 onFullscreen call backs are never fired
#3040 [Bug] Fullscreen broken on iOS due to #3017
#2744 Unblock the main thread while replacing the source (cf comment)

[freeboub]

thank for this PR, it looks good except #2744 Unblock the main thread while replacing the source (#2744 (comment))

We already experiment this change, but it causes crash when fast changing source...
can you revert this change and I will merge this soon.

The good fix has be be discussed (I think I know the good fix but this is a big architecture change ...)

[cguino]

Thank you, I revert #2744

[marcel-happyfloat]

@freeboub the main thread blocking makes this library unusable for us in the real world with bad internet connection trying to scroll a feed of video items. Do you think the fix is safe to use for multiple video elements, with only one fixed source at a time? (or mounting/unmounting with new source). Thank you.
I really appreciate all your work, unfortunately I can't help debugging on the native side.

[Trashpants]

Also in the same boat with the blocking main thread, without knowing too much about the internals can we have this as an optional so additional prop such as dangerouslySwapIosVideoSource as a bool on the player component?

[freeboub]

I totally understand the issue of startup I revert following change: 1f27ffb
which was causing the crash. I really think it will cause the same issue.
This code also causes an issue when rapidly changing source...
There is clearly a concurrency issue in react native video.
I fixed it on android in my company fork but it is a nightmare to backport, I need to find time to reimplement it here.
moreover the PR of new arch will also conflict with it :/
Let see.
Notice that I advise you to patch the package (with patch-package) or create your own fork if you really want this change.
Personally I prefer latency than crash ...