[uievents] Fire keydown/keyup during composition (#75)

>From the thread starting at http://lists.w3.org/Archives/Public/public-webapps/2016JanMar/0024.html

@rniwa:
> We've [Apple, Google, Microsoft] been informed that Gecko/Firefox does not fire keydown/keyup events during input method composition for each key stroke.  Could someone from Mozilla clarify why this is desirable behavior?
>
> We think it's better to fire keydown/keyup events for consistency across browsers.

@masayuki-nakano:
> For the compatibility between other browsers, I agree with changing Gecko's behavior.
> 
> However, there is an important thing is, which key value is proper value for keyboard events during composition. For example, in Kana input mode of Japanese IME, ASCII characters vs. Kana characters. Due to the platform limitations, browsers cannot retrieve what character *will* be inputted into the composition string.
> 
> At a meeting of UI Events (or D3E Events), we discussed this issue. IIRC, at that time, we didn't find any proper value but browsers should *not* dispatch keyboard events during composition (but allowing it for backward compatibility for non-Gecko browsers, therefore, currently defined with MAY).
> 
> I believe that web authors shouldn't handle keyboard events for text input. I.e., shouldn't need keyboard events during composition because such applications cannot support handwriting system and/or speech input system. At least spec should recommend web authors should handle "compositionupdate", "beforeinput" and/or "input". Handling  keydown/keyup event during composition means that a keydown/keyup event causes double action (default action, i.e., modifying composition string  and web app specific action).

Mozilla's tracking bug for this: https://bugzilla.mozilla.org/show_bug.cgi?id=354358

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/uievents/issues/75