Unback out and reland changeset a1223ec7312a (bug 987026) because it wasn't at fault for the mochitest failures on a CLOSED TREE

accessible/src/base/FocusManager.cpp

@@ -240,9 +240,11 @@ FocusManager::ProcessDOMFocus(nsINode* aTarget)
 
   DocAccessible* document =
     GetAccService()->GetDocAccessible(aTarget->OwnerDoc());
+  if (!document)
+    return;
 
   Accessible* target = document->GetAccessibleEvenIfNotInMapOrContainer(aTarget);
-  if (target && document) {
+  if (target) {
     // Check if still focused. Otherwise we can end up with storing the active
     // item for control that isn't focused anymore.
     nsINode* focusedNode = FocusedDOMNode();