Shouldn't be able to scroll clipped content

[GoogleCodeExporter]

After landing overflow, the mousewheel mistakenly scrolls clipped content.
Sometimes this has the effect of making the content "disappear" as the
mouse touches it. I think I remember a Bugzilla entry about this somewhere.

Original issue reported on code.google.com by classi...@floodgap.com on 22 Jan 2010 at 5:59

[GoogleCodeExporter]

Upgrading to critical. This touches too many sites.

Original comment by classi...@floodgap.com on 26 Jan 2010 at 6:22

• Added labels: Priority-Critical
• Removed labels: Priority-High

[GoogleCodeExporter]

Fixed in nsEventStateManager.cpp. Although I started with M259615, I ended up
scrapping it and writing something entirely newer and simpler. Simply blocking 
any
frame that comes up OVERFLOW_CLIP, _HIDDEN or _VISIBLE blocks *everything* 
because
the body is also _VISIBLE overflow. This code checks the scroll frame style, 
and if
it's one of those, checks to see if (if it's _VISIBLE) a BODY or HTML entity. 
If it
is, it lets the scroll event through and blocks the rest. This seems 
satisfactory.

Incidentally, changing body to overflow:auto in html.css didn't make any 
difference
and I'd really rather not be messing with the global style sheets anyway.

Original comment by classi...@floodgap.com on 29 Jan 2010 at 9:33

• Changed state: Fixed