Handle pointerlock rejections, if promise based

[852Kerfunkle]

This should get rid of the unhandled top-level exception if requesting pointer lock fails.

I think the intended way to use pointer lock in Babylon is to sub to onCanvasBlurObservable and onCanvasFocusObservable, so element.focus() probably belongs into the resolved handler.

The alternative would be to focus regardless, but this is probably not desired:

if (promise instanceof Promise) promise.catch(() => {});
element.focus();

A good way to try this behaviour is to enter and exit pointerlock in quick succession on a chromium based browser.

[bjsplat]

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[bjsplat]

Snapshot stored with reference name:
refs/pull/13487/merge

Test environment:
https://babylonsnapshots.z22.web.core.windows.net/refs/pull/13487/merge/index.html

To test a playground add it to the URL, for example:

https://babylonsnapshots.z22.web.core.windows.net/refs/pull/13487/merge/index.html#WGZLGJ#4600

Links to test babylon tools with this snapshot:

https://playground.babylonjs.com/?snapshot=refs/pull/13487/merge
https://sandbox.babylonjs.com/?snapshot=refs/pull/13487/merge
https://gui.babylonjs.com/?snapshot=refs/pull/13487/merge
https://nme.babylonjs.com/?snapshot=refs/pull/13487/merge

To test the snapshot in the playground with a playground ID add it after the snapshot query string:

https://playground.babylonjs.com/?snapshot=refs/pull/13487/merge#BCU1XR#0

[852Kerfunkle]

Well, it fails in a pretty unrelated test. To be honest: no idea.

Neither Engine.enterPointerlock nor Engine._RequestPointerlock should be called anywhere near this (unless these tests are somehow run in fullscreen, not that I could find anything like it).

Anecdotal evidence: I've been doing this for months now and no Safari user ever complained. I mean, they complain quite a bit, just not about this specifically. :)

It's not really important, this unhandled exception just kept bugging me.

[RaananW]

No modern browser is synchronous anymore. Chrome/edge from 92, firefox and iOS as well.
Great catch :-)

[852Kerfunkle]

No modern browser is synchronous anymore. Chrome/edge from 92, firefox and iOS as well. Great catch :-)

Last I checked firefox still returns undefined, but maybe that changed since I last checked. :)