The page at http://themaninblue.com/experiment/AnimationBenchmark/canvas/ is able to starve the idle that is responsible for redrawing in GTK+. We need to further fine tune the priorities we use in our various timeouts.
Created attachment 64383 [details] proposed fix This fixes the issue with that site for me, even with the browser under great stress, such as playing flash videos, some chromeexperiments, the "video blow up" demo, and playing http://trailers.apple.com/movies/paramount/ironman2/ironman2-34rgrwt9-tlr2_720p.mov. The priority used is the one GTK+ uses for its redraw idle.
Wow! That was a fast fix. Maybe you should change the priority to GDK_PRIORITY_REDRAW? http://library.gnome.org/devel/gdk/stable/gdk-Events.html#GDK-PRIORITY-REDRAW:CAPS
I could, but then I'd need to add the gdk include to this file, do you think it's worth it? =)
Hrm. My preference is either the GDK include or a comment explaining where the "+ 20" comes from.
I landed this as r65438 adding the include. Thanks for the reviews!
http://trac.webkit.org/changeset/65438 might have broken SnowLeopard Intel Release (Tests)