Add an experimental permissions API for extensions.

chrome/common/extensions/url_pattern_set.h

 // Copyright (c) 2011 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_URL_PATTERN_SET_H_
 #define CHROME_COMMON_EXTENSIONS_URL_PATTERN_SET_H_
 #pragma once
 
 #include <set>
 
 #include "chrome/common/extensions/url_pattern.h"
 
 class GURL;
 
 // Represents the set of URLs an extension uses for web content.
 class URLPatternSet {
  public:
   typedef std::set<URLPattern>::const_iterator const_iterator;
   typedef std::set<URLPattern>::iterator iterator;
 
+  // Clears |out| and populates the set with |set1| - |set2|.
+  static void CreateDifference(const URLPatternSet& set1,
+                               const URLPatternSet& set2,
+                               URLPatternSet* out);
+
+  // Clears |out| and populates the set with the intersection of |set1|
+  // and |set2|.
+  static void CreateIntersection(const URLPatternSet& set1,
+                                 const URLPatternSet& set2,
+                                 URLPatternSet* out);
+
   // Clears |out| and populates the set with the union of |set1| and |set2|.
   static void CreateUnion(const URLPatternSet& set1,
                           const URLPatternSet& set2,
                           URLPatternSet* out);
 
   URLPatternSet();
   URLPatternSet(const URLPatternSet& rhs);
   explicit URLPatternSet(const std::set<URLPattern>& patterns);
   ~URLPatternSet();
 
   URLPatternSet& operator=(const URLPatternSet& rhs);
   bool operator==(const URLPatternSet& rhs) const;
 
   bool is_empty() const;
   const std::set<URLPattern>& patterns() const { return patterns_; }
   const_iterator begin() const { return patterns_.begin(); }
   const_iterator end() const { return patterns_.end(); }
 
   void AddPattern(const URLPattern& pattern);
   void ClearPatterns();
 
+  // Returns true if the permission |set| is a subset of this.
+  bool Contains(const URLPatternSet& set) const;
+
   // Test if the extent contains a URL.
   bool MatchesURL(const GURL& url) const;
 
   // Returns true if there is a single URL that would be in two extents.
   bool OverlapsWith(const URLPatternSet& other) const;
 
  private:
   // The list of URL patterns that comprise the extent.
   std::set<URLPattern> patterns_;
 };
 
 #endif  // CHROME_COMMON_EXTENSIONS_URL_PATTERN_SET_H_