Sync the launch type pref for apps.

chrome/browser/extensions/launch_util.h

 // Copyright (c) 2013 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_LAUNCH_UTIL_H_
 #define CHROME_BROWSER_EXTENSIONS_LAUNCH_UTIL_H_
 
 #include <string>
 
 #include "chrome/common/extensions/extension_constants.h"
 
+class ExtensionService;
+
 namespace extensions {
 
 class Extension;
 class ExtensionPrefs;
 
 // Gets the launch type preference. If no preference is set, returns
 // LAUNCH_TYPE_DEFAULT.
 // Returns LAUNCH_TYPE_WINDOW if there's no preference and
 // 'streamlined hosted apps' are enabled.
 LaunchType GetLaunchType(const ExtensionPrefs* prefs,
                          const Extension* extension);
 
-// Sets an extension's launch type preference.
-void SetLaunchType(ExtensionPrefs* prefs,
+// Returns the LaunchType that is set in the prefs. Returns LAUNCH_TYPE_INVALID
+// if no value is set in prefs.
+LaunchType GetLaunchTypePrefValue(const ExtensionPrefs* prefs,
+                                  const std::string& extension_id);
+
+// Sets an extension's launch type preference and syncs the value if necessary.
+void SetLaunchType(ExtensionService* prefs,
                    const std::string& extension_id,
                    LaunchType launch_type);
 
 // Finds the right launch container based on the launch type.
 // If |extension|'s prefs do not have a launch type set, then the default
 // value from GetLaunchType() is used to choose the launch container.
 LaunchContainer GetLaunchContainer(const ExtensionPrefs* prefs,
                                    const Extension* extension);
 
 // Returns true if a launch container preference has been specified for
 // |extension|. GetLaunchContainer() will still return a default value even if
 // this returns false.
 bool HasPreferredLaunchContainer(const ExtensionPrefs* prefs,
                                  const Extension* extension);
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_LAUNCH_UTIL_H_