Fixes #2069. Enable KeyDown and KeyUp events to be canceled (like KeyPress)

[BDisp]

Fixes #2069 - Now it's possible to cancel any key on the KeyDown and KeyUp events, like KeyPress event does.

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[tig]

@BDisp we got a merge conflict. Can you fix please?

[BDisp]

@BDisp we got a merge conflict. Can you fix please?

Done @tig.