Exempt component and policy-installed extensions from policy blacklist check.

chrome/browser/extensions/extension_prefs.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_BROWSER_EXTENSIONS_EXTENSION_PREFS_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_PREFS_H_
 #pragma once
 
 #include <set>
 #include <string>
@@ skipping 155 matching lines @@
   // Returns true if the extension notification code has already run for the
   // first time for this profile. Currently we use this flag to mean that any
   // extensions that would trigger notifications should get silently
   // acknowledged. This is a fuse. Calling it the first time returns false.
   // Subsequent calls return true. It's not possible through an API to ever
   // reset it. Don't call it unless you mean it!
   bool SetAlertSystemFirstRun();
 
   // Is the extension with |extension_id| allowed by policy (checking both
   // whitelist and blacklist).
-  bool IsExtensionAllowedByPolicy(const std::string& extension_id);
+  bool IsExtensionAllowedByPolicy(const std::string& extension_id,
+                                  Extension::Location location);
 
   // Returns the last value set via SetLastPingDay. If there isn't such a
   // pref, the returned Time will return true for is_null().
   base::Time LastPingDay(const std::string& extension_id) const;
 
   // The time stored is based on the server's perspective of day start time, not
   // the client's.
   void SetLastPingDay(const std::string& extension_id, const base::Time& time);
 
   // Similar to the 2 above, but for the extensions blacklist.
@@ skipping 330 matching lines @@
 
   // Weak pointer, owned by Profile.
   ExtensionPrefValueMap* extension_pref_value_map_;
 
   scoped_refptr<ExtensionContentSettingsStore> content_settings_store_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionPrefs);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_PREFS_H_