Simplify the Observer pattern used in the BrowserList.

base/observer_list.h

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 BASE_OBSERVER_LIST_H__
 #define BASE_OBSERVER_LIST_H__
 
 #include <algorithm>
 #include <limits>
 #include <vector>
 
@@ skipping 130 matching lines @@
     if (notify_depth_) {
       for (typename ListType::iterator it = observers_.begin();
            it != observers_.end(); ++it) {
         *it = 0;
       }
     } else {
       observers_.clear();
     }
   }
 
+  size_t size() const { return observers_.size(); }
+
  protected:
-  size_t size() const {
-    return observers_.size();
-  }
-
   void Compact() {
     typename ListType::iterator it = observers_.begin();
     while (it != observers_.end()) {
       if (*it) {
         ++it;
       } else {
         it = observers_.erase(it);
       }
     }
   }
@@ skipping 33 matching lines @@
 
 #define FOR_EACH_OBSERVER(ObserverType, observer_list, func)  \
   do {                                                        \
     ObserverListBase<ObserverType>::Iterator it(observer_list);   \
     ObserverType* obs;                                        \
     while ((obs = it.GetNext()) != NULL)                      \
       obs->func;                                              \
   } while (0)
 
 #endif  // BASE_OBSERVER_LIST_H__