When parsing a full doc from a string, nsHtml5TreeOpExecutor unblocks onload an extra time and causes an assertion. Layout start and scroll to ref code unnecessary, too.
Created attachment 591715 [details] [diff] [review]
Return earlier from DidBuildModel when working for an nsHtml5StringParser
We didn't have enough DOMParser reftest/crashtest coverage to catch the assertion earlier.
Thanks for the r+.