Bug 485808. Create an iterator class to do forward iteration over the result of GetChildArray(). r+sr=sicking

content/base/src/nsGenericElement.cpp

@@ -173,6 +173,8 @@ NS_DEFINE_IID(kThisPtrOffsetsSID, NS_THISPTROFFSETS_SID);
 
 PRInt32 nsIContent::sTabFocusModel = eTabFocus_any;
 PRBool nsIContent::sTabFocusModelAppliesToXUL = PR_FALSE;
+PRUint32 nsMutationGuard::sMutationCount = 0;
+
 nsresult NS_NewContentIterator(nsIContentIterator** aInstancePtrResult);
 
 //----------------------------------------------------------------------
@@ -5123,17 +5125,10 @@ TryMatchingElementsInSubtree(nsINode* aRoot,
   char databuf[2 * sizeof(RuleProcessorData)];
   RuleProcessorData* prevSibling = nsnull;
   RuleProcessorData* data = reinterpret_cast<RuleProcessorData*>(databuf);
-  PRUint32 count;
-  nsIContent * const * kidSlot = aRoot->GetChildArray(&count);
-  nsIContent * const * end = kidSlot + count;
 
-#ifdef DEBUG
-  nsMutationGuard debugMutationGuard;
-#endif
-  
   PRBool continueIteration = PR_TRUE;
-  for (; kidSlot != end; ++kidSlot) {
-    nsIContent* kid = *kidSlot;
+  for (nsINode::ChildIterator iter(aRoot); !iter.IsDone(); iter.Next()) {
+    nsIContent* kid = iter;
     if (!kid->IsNodeOfType(nsINode::eELEMENT)) {
       continue;
     }
@@ -5193,10 +5188,6 @@ TryMatchingElementsInSubtree(nsINode* aRoot,
     prevSibling->~RuleProcessorData();
   }
 
-#ifdef DEBUG
-  NS_ASSERTION(!debugMutationGuard.Mutated(0), "Unexpected mutations happened");
-#endif
-
   return continueIteration;
 }