today that image urls weren't properly getting added to the doc loader of the containing document. So the top
level document would report a document done notification before the document may really be done.
The fix is to pass the load cookie nsISupports object which originates from the docshell that is opening the
url down into the gfx image code instead of passing the load group down.
r=travis.
git-svn-id: svn://10.0.0.236/trunk@60802 18797224-902f-48f8-a5cc-f745e15eee43
df3dddf528