Be a little more careul with inheriting principals. Bug 304690, r=dveditz,

sr=jst

docshell/base/nsDocShell.cpp

@@ -6370,7 +6370,9 @@ nsDocShell::InternalLoad(nsIURI * aURI,
     //
     {
         PRBool inherits;
-        if (!owner && (aFlags & INTERNAL_LOAD_FLAGS_INHERIT_OWNER) &&
+        // One more twist: Don't inherit the owner for external loads.
+        if (aLoadType != LOAD_NORMAL_EXTERNAL && !owner &&
+            (aFlags & INTERNAL_LOAD_FLAGS_INHERIT_OWNER) &&
             NS_SUCCEEDED(URIInheritsSecurityContext(aURI, &inherits)) &&
             inherits) {
             owner = GetInheritedPrincipal(PR_TRUE);