[GUI] deal with dead codes correctly

[RaananW]

Playground: #I1Y5YT#47

This treats dead code as expected minus a few modifiers that are not available in a keyboard event. For example - on a supporting keyboard - when entering a quote (") and A afterwards we should output ä, but the expected result if entering " and f (for example) afterwards is: "f. This is not provided in the event. Threfore we are using the default behavior, which is output the dead key if space was entered right after.

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[carolhmj]

Just some console logs in the wild otherwise very nice! :D