Provide a mechanism to the decl. WebRequest API to match URLs without the query against a RegEx

extensions/common/matcher/regex_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 EXTENSIONS_COMMON_MATCHER_REGEX_SET_MATCHER_H_
 #define EXTENSIONS_COMMON_MATCHER_REGEX_SET_MATCHER_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 25 matching lines @@
   void AddPatterns(const std::vector<const StringPattern*>& regex_list);
 
   // Removes all regex patterns.
   void ClearPatterns();
 
   // Appends the IDs of regular expressions in our set that match the |text|
   // to |matches|.
   bool Match(const std::string& text,
              std::set<StringPattern::ID>* matches) const;
 
+  bool IsEmpty() const;
+
  private:
   typedef int RE2ID;
   typedef std::map<StringPattern::ID, const StringPattern*> RegexMap;
   typedef std::vector<StringPattern::ID> RE2IDMap;
 
   // Use Aho-Corasick SubstringSetMatcher to find which literal patterns
   // match the |text|.
   std::vector<RE2ID> FindSubstringMatches(const std::string& text) const;
 
   // Rebuild FilteredRE2 from scratch. Needs to be called whenever
@@ skipping 15 matching lines @@
   scoped_ptr<SubstringSetMatcher> substring_matcher_;
 
   // The substring patterns from FilteredRE2, which are used in
   // |substring_matcher_| but whose lifetime is managed here.
   std::vector<const StringPattern*> substring_patterns_;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_MATCHER_REGEX_SET_MATCHER_H_