Patch forthcoming.
Created attachment 59106 [details] Fix an apparent typo in HTMLScriptElement::isURLAttribute()
Comment on attachment 59106 [details] Fix an apparent typo in HTMLScriptElement::isURLAttribute() r=me!
Fixed in <http://trac.webkit.org/projects/webkit/changeset/61410>.
I am reworking r61379, which I guess I had not tested sufficiently before! My patch included this fix, and I am glad it has been separately dealt with. Along with this problem, I discovered that HTMLMediaElement is also missing isURLAttribute for the src attribute on <video> and <audio> elements.