[whatwg] Additional onxxxx event attributes for DOM Level3 Events

[Hajime Morita]

Hi,

I noticed that some events which are defined in DOM Level3 Events [1] don't have
associated HTML attributes.
For example, "keypress" event has associated "onkeypress" attribute.
But "focusin" event doesn't have "onfocusin" attribute.

Here is a list:

* wheel event
* textInput event
* focusin event
* focusout event
* compositionstart event
* compositionupdate event
* compositionend event
* DOMXxxx events

I think these events should have associated attributes defined.
DOM mutation events might be better to skip due to its long name and rare usage.
But it's just a preference and not a strong opinion.

How do you think?

Regards.
-- 
morita