Initial Managed Mode extension API, supporting querying the setting and a stub for enabling the mod…

chrome/browser/extensions/extension_preference_api.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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_EXTENSION_PREFERENCE_API_H__
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_PREFERENCE_API_H__
 #pragma once
 
 #include <string>
 
 #include "chrome/browser/extensions/extension_function.h"
@@ skipping 47 matching lines @@
       bool* bad_message) = 0;
 
   // Converts the representation of the preference as stored in the browser
   // into a representation that is used by the extension.
   // Returns the extension representation in case of success or NULL otherwise.
   // The ownership of the returned value is passed to the caller.
   virtual base::Value* BrowserToExtensionPref(
       const base::Value* browser_pref) = 0;
 };
 
-class GetPreferenceFunction : public SyncExtensionFunction {
+// A base class to provide functionality common to the other *PreferenceFunction
+// classes.
+class PreferenceFunction : public SyncExtensionFunction {
+ public:
+  virtual ~PreferenceFunction();
+
+ protected:
+  // Given an |extension_pref_key|, provides its |browser_pref_key| from the
+  // static map in extension_preference.cc. Returns true if the corresponding
+  // browser pref exists and the extension has the API permission needed to
+  // modify that pref. Sets error_ if the extension doesn't have the needed

[Bernhard Bauer, 2012/03/02 09:23:59]

Tiny nit: |error_|

+  // permission.
+  bool ValidateBrowserPref(std::string extension_pref_key,
+                           std::string* browser_pref_key);
+};
+
+class GetPreferenceFunction : public PreferenceFunction {
  public:
   virtual ~GetPreferenceFunction();
   virtual bool RunImpl() OVERRIDE;
   DECLARE_EXTENSION_FUNCTION_NAME("types.ChromeSetting.get")
 };
 
-class SetPreferenceFunction : public SyncExtensionFunction {
+class SetPreferenceFunction : public PreferenceFunction {
  public:
   virtual ~SetPreferenceFunction();
   virtual bool RunImpl() OVERRIDE;
   DECLARE_EXTENSION_FUNCTION_NAME("types.ChromeSetting.set")
 };
 
-class ClearPreferenceFunction : public SyncExtensionFunction {
+class ClearPreferenceFunction : public PreferenceFunction {
  public:
   virtual ~ClearPreferenceFunction();
   virtual bool RunImpl() OVERRIDE;
   DECLARE_EXTENSION_FUNCTION_NAME("types.ChromeSetting.clear")
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_PREFERENCE_API_H__