Replace Excalibur promise implementation with browser implementation

[eonarheim]

Context

Currently we have a basic functioning custom promise implementation, but this prevents new browser features like async/await from working natively. Additionally we will get a bunch of promise features for free by switching to native promises. It may also come with a bonus of closing these #533 #365 #341

Proposal

• Add the tsconfig native promise polyfill option lib: ES2018.Promise
• For backwards compatibility for other games, change ex.Promise implementation to wrap the native one.
• Replace existing methods in excalibur that use ex.Promise and use the native Promise returns (this will be a breaking change, unless use the ex.Promise wrapper, there can be no easy transition unless we rename methods)

[LoserAntbear]

Looks like we also need to add lib: [es2015, dom]. Because es2018.Promise adds final method to Promise interface, defined in es2015.promise PromiseConstructor, if i understand this right.
BTW, I already made this changes and also replaced all uses of ex.Promise with native es6-promise and ready to push here. But i am a bit confused with providing backwards compatibility to ex.Promise. Now i just added as prop ex.Promise._nativePromise which resolves on ex.Promise.resolve and rejects on ex.Promise.reject, but i feel it is not the way it is meant to be. :)

[LoserAntbear]

Hello again! I am sorry, bear with me. :D Could you look into this, please?

[eonarheim]

@LoserAntbear Adding lib: [es2015, dom] makes sense to me.

Please send a PR, as long as the new implementation of ex.Promise backed by the _nativePromise behaves in a similar way to the old one (the tests should be a good indicator) that's what we want.

[kamranayub]

You could be even more specific I think and do es2015.promise or something like that.

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On Wed, Jun 13, 2018, 06:41 Erik Onarheim ***@***.***> wrote: @LoserAntbear <https://github.com/LoserAntbear> Adding lib: [es2015, dom] makes sense to me. Please send a PR, as long as the new implementation of ex.Promise backed by the _nativePromise behaves in a similar way to the old one (the tests should be a good indicator) that's what we want. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#994 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAiaazzM7l-QRtCdaSJCHrJtUv6UE-Vbks5t8PpNgaJpZM4UJLMu> .