I've open an upstream bug with a patch: http://code.google.com/p/chromium/issues/detail?id=63981 I guess it might be interesting to have this patch applied in the Gentoo ebuild.
Thank you, the patch generally looks fine. However, we should really apply it upstream, and the way to do that is described on http://www.chromium.org/developers/contributing-code I am also an upstream developer, so I'd be glad to help you with the submission.