Add a separate cookie store that's used for extensions....

net/base/cookie_monster.h

Index: net/base/cookie_monster.h
===================================================================
--- net/base/cookie_monster.h	(revision 15945)
+++ net/base/cookie_monster.h	(working copy)
@@ -76,6 +76,7 @@
         store_(NULL),
         last_access_threshold_(
             base::TimeDelta::FromSeconds(last_access_threshold_seconds)) {
+    SetDefaultCookieableSchemes();
   }
 #endif
 
@@ -133,9 +134,15 @@
                     const CanonicalCookie& cookie,
                     bool sync_to_store);
 
+  // Override the default list of schemes that are allowed to be set in
+  // this cookie store.  Calling his overrides the value of
+  // "enable_file_scheme_".
+  void SetCookieableSchemes(const char* schemes[], size_t num_schemes);
+
   // There are some unknowns about how to correctly handle file:// cookies,
   // and our implementation for this is not robust enough. This allows you
   // to enable support, but it should only be used for testing. Bug 1157243.
+  // Must be called before creating a CookieMonster instance.
   static void EnableFileScheme();
   static bool enable_file_scheme_;
 
@@ -156,6 +163,8 @@
   // Should only be called by InitIfNecessary().
   void InitStore();
 
+  void SetDefaultCookieableSchemes();
+
   void FindCookiesForHostAndDomain(const GURL& url,
                                    const CookieOptions& options,
                                    std::vector<CanonicalCookie*>* cookies);
@@ -210,6 +219,8 @@
                             const CookieMapItPair& itpair,
                             std::vector<CookieMap::iterator>* cookie_its);
 
+  bool HasCookieableScheme(const GURL& url);
+
   CookieMap cookies_;
 
   // Indicates whether the cookie store has been initialized. This happens
@@ -227,6 +238,8 @@
   // update it again.
   const base::TimeDelta last_access_threshold_;
 
+  std::vector<std::string> cookieable_schemes_;
+
   // Lock for thread-safety
   Lock lock_;