Make NodeIterator more STL-friendly.

content/browser/frame_host/frame_tree.h

 // Copyright 2013 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.
 
 #ifndef CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_
 #define CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_
 
 #include <stdint.h>
 
+#include <iterator>
 #include <string>
 
 #include "base/callback.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/browser/frame_host/frame_tree_node.h"
 #include "content/common/content_export.h"
 
 namespace content {
@@ skipping 15 matching lines @@
 // page navigations.
 //
 // TODO(ajwong): Move NavigationController ownership to the main frame
 // FrameTreeNode. Possibly expose access to it from here.
 //
 // This object is only used on the UI thread.
 class CONTENT_EXPORT FrameTree {
  public:
   class NodeRange;
 
-  class CONTENT_EXPORT NodeIterator {
+  class CONTENT_EXPORT NodeIterator
+      : public std::iterator<std::forward_iterator_tag, FrameTreeNode> {
    public:
     ~NodeIterator();
 
     NodeIterator& operator++();
 
     bool operator==(const NodeIterator& rhs) const;
     bool operator!=(const NodeIterator& rhs) const { return !(*this == rhs); }
 
     FrameTreeNode* operator*() { return current_node_; }
 
@@ skipping 190 matching lines @@
 
   // Overall load progress.
   double load_progress_;
 
   DISALLOW_COPY_AND_ASSIGN(FrameTree);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_