Followup to r177831.

Source/core/inspector/InspectorNodeIds.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/inspector/InspectorNodeIds.h"
 
 #if ENABLE(OILPAN)
 #include "core/dom/Node.h"
 #else
@@ skipping 19 matching lines @@
     return *idToNodeMap;
 }
 
 int InspectorNodeIds::idForNode(Node* node)
 {
     static int s_nextNodeId = 1;
     NodeToIdMap::iterator it = nodeToIdMap().find(node);
     if (it != nodeToIdMap().end())
         return it->value;
     int id = s_nextNodeId++;
-    it->value = id;
+    nodeToIdMap().set(node, id);
     ASSERT(idToNodeMap().find(id) == idToNodeMap().end());
     idToNodeMap().set(id, node);
     return id;
 }
 
 Node* InspectorNodeIds::nodeForId(int id)
 {
     return idToNodeMap().get(id);
 }
 #else
@@ skipping 15 matching lines @@
     return result;
 }
 
 Node* InspectorNodeIds::nodeForId(int id)
 {
     return nodeIds().node(id);
 }
 #endif
 
 }