Revert 143896 - Filtered events.

chrome/common/extensions/value_counter.h

-// Copyright (c) 2012 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 CHROME_COMMON_EXTENSIONS_VALUE_COUNTER_H_
-#define CHROME_COMMON_EXTENSIONS_VALUE_COUNTER_H_
-#pragma once
-
-#include "base/memory/linked_ptr.h"
-
-#include <vector>
-
-namespace base {
-class Value;
-}
-
-namespace extensions {
-
-// Keeps a running count of Values, like map<Value, int>. Adding / removing
-// values increments / decrements the count associated with a given Value.
-//
-// Add() and Remove() are linear in the number of Values in the ValueCounter,
-// because there is no operator<() defined on Value, so we must iterate to find
-// whether a Value is equal to an existing one.
-class ValueCounter {
- public:
-  ValueCounter();
-  ~ValueCounter();
-
-  // Adds |value| to the set and returns how many equal values are in the set
-  // after. Does not take ownership of |value|. In the case where a Value equal
-  // to |value| doesn't already exist in this map, this function makes a
-  // DeepCopy() of |value|.
-  int Add(const base::Value& value);
-
-  // Removes |value| from the set and returns how many equal values are in
-  // the set after.
-  int Remove(const base::Value& value);
-
-  // Same as Add() but only performs the add if the value isn't present.
-  int AddIfMissing(const base::Value& value);
-
- private:
-  class Entry {
-   public:
-    explicit Entry(const base::Value& value);
-    ~Entry();
-
-    int Increment();
-    int Decrement();
-
-    const base::Value* value() const { return value_.get(); }
-    int count() const { return count_; }
-
-   private:
-    linked_ptr<base::Value> value_;
-    int count_;
-
-    DISALLOW_COPY_AND_ASSIGN(Entry);
-  };
-  typedef std::vector<linked_ptr<Entry> > EntryList;
-
-  int AddImpl(const base::Value& value, bool increment);
-
-  EntryList entries_;
-
-  DISALLOW_COPY_AND_ASSIGN(ValueCounter);
-};
-
-}  // namespace extensions
-
-#endif  // CHROME_COMMON_EXTENSIONS_VALUE_COUNTER_H_