Fixed a case where the KeyUp event is not called by Command+Key on MacOS

[zuvola]

Fixes flutter/flutter#133832

The KeyUp event was not being called when the first responder was the FlutterViewWrapper.

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[knopp]

I don't know if this is the correct solution. Why is FlutterViewWrapper first responder in the first place?

[zuvola]

@knopp
FlutterTextInputPlugin sets self.nextResponder as first responder, so FlutterViewWrapper, the parent of FlutterTextInputPlugin, becomes the first responder It seems to be the case.

https://github.com/flutter/engine/blob/727fd967973a931bd24f331ec31ad928ab285b37/shell/platform/darwin/macos/framework/Source/FlutterTextInputPlugin.mm#L384-L392

Should I have fixed the resignAndRemoveFromSuperview?

[knopp]

I'm not sure what the correct solution is here, I will look into it, but I think the responder chain should be consistent before and after text input plugin is added/removed from hierarchy.

[knopp]

I don't think this is correct solution. The problem here is that firstResponder is not being consistent, which should be fixed by #46032.

[zuvola]

Ok, I understand. Thanks for the correction.