Unset stopPropagationFlags due to latest DOM spec changes
Unset stopPropagationFlags due to latest DOM spec changes

See #1501 and nested issues for more details.

mzgol/jsdom,snuggs/jsdom,Zirro/jsdom,Zirro/jsdom,fiftin/jsdom,tmpvar/jsdom,Joris-van-der-Wel/jsdom,Joris-van-der-Wel/jsdom,mzgol/jsdom,Joris-van-der-Wel/jsdom,fiftin/jsdom,mzgol/jsdom,snuggs/jsdom,fiftin/jsdom,tmpvar/jsdom