Implement rules removal for WebRequestRulesRegistry

chrome/browser/extensions/api/declarative/substring_set_matcher.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_SUBSTRING_SET_MATCHER_H_
 #define CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_SUBSTRING_SET_MATCHER_H_
 #pragma once
 
 #include <map>
 #include <set>
@@ skipping 50 matching lines @@
   void RegisterAndUnregisterPatterns(
       const std::vector<const SubstringPattern*>& to_register,
       const std::vector<const SubstringPattern*>& to_unregister);
 
   // Matches |text| against all registered SubstringPatterns. Stores the IDs
   // of matching patterns in |matches|. |matches| is not cleared before adding
   // to it.
   bool Match(const std::string& text,
              std::set<SubstringPattern::ID>* matches) const;
 
+  // Returns true if this object retains no allocated data. Only for debugging.
+  bool IsCompletelyEmpty() const;

[Matt Perry, 2012/03/28 18:59:52]

nit: IsEmpty should be fine... I wouldn't expect it to return true if it's only
half empty :)

[battre, 2012/03/28 19:18:42]

Done.

+
  private:
   // A node of an Aho Corasick Tree. This is implemented according to
   // http://www.cs.uku.fi/~kilpelai/BSA05/lectures/slides04.pdf
   //
   // The algorithm is based on the idea of building a trie of all registered
   // patterns. Each node of the tree is annotated with a set of pattern
   // IDs that are used to report matches.
   //
   // The root of the trie represents an empty match. If we were looking whether
   // any registered pattern matches a text at the beginning of the text (i.e.
@@ skipping 68 matching lines @@
 
   // The nodes of a Aho-Corasick tree.
   std::vector<AhoCorasickNode> tree_;
 
   DISALLOW_COPY_AND_ASSIGN(SubstringSetMatcher);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_SUBSTRING_SET_MATCHER_H_