Implement rules removal for WebRequestRulesRegistry

chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry.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_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_RULES_REGISTRY_H_
 #define CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_RULES_REGISTRY_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 51 matching lines @@
   virtual std::string AddRulesImpl(
       const std::string& extension_id,
       const std::vector<linked_ptr<RulesRegistry::Rule> >& rules) OVERRIDE;
   virtual std::string RemoveRulesImpl(
       const std::string& extension_id,
       const std::vector<std::string>& rule_identifiers) OVERRIDE;
   virtual std::string RemoveAllRulesImpl(
       const std::string& extension_id) OVERRIDE;
   virtual content::BrowserThread::ID GetOwnerThread() const OVERRIDE;
 
+  // Returns true if this object retains no allocated data. Only for debugging.
+  bool IsEmpty() const;
+
  private:
   // Map that tells us which WebRequestRule may match under the condition that
   // the URLMatcherConditionSet::ID was returned by the |url_matcher_|.
   typedef std::map<URLMatcherConditionSet::ID, WebRequestRule*> RuleTriggers;
   RuleTriggers rule_triggers_;
 
   typedef std::map<WebRequestRule::GlobalRuleId, linked_ptr<WebRequestRule> >
       RulesMap;
   RulesMap webrequest_rules_;
 
   URLMatcher url_matcher_;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_RULES_REGISTRY_H_