Re: [uievents] Specify MouseEvent.which (#35)

Followup: 
I didn't have the full picture before... Notes from the fellow who reduced this issue:

The YUI event wrapper has this code in its init function:
```js
var e = this._event, t = this._wrapper.overrides, r = e.pageX, o = e.pageY, u, a = this._currentTarget;
            this.altKey = e.altKey,
            this.ctrlKey = e.ctrlKey,
            this.metaKey = e.metaKey,
            this.shiftKey = e.shiftKey,
            this.type = t && t.type || e.type,
            this.clientX = e.clientX,
            this.clientY = e.clientY,
            this.pageX = r,
            this.pageY = o,
            u = e.keyCode || e.charCode,
            n.webkit && u in i && (u = i[u]),
            this.keyCode = u,
            this.charCode = u,
            this.which = e.which || e.charCode || u,
            this.button = this.which
```
The key here is that if keycode or charcode are undefined, the “which” property of the wrapper will be undefined as well (0 || undefined || undefined resolves to undefined in js).

This will cause zillow’s logic to still get undefined for which and fail their logic.

As users just updated from Chrome 45 to 46, we just confirmed that Zillow will not work as well anymore in Chrome. Specifically, this is what we are finding: the map resets its location as you try to pan -- multiple swipes will reset the map position each time rather than continuing to progress along the map.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/uievents/issues/35#issuecomment-148499534