Don't persist registrations for whitelists installed from the command line.

chrome/browser/component_updater/supervised_user_whitelist_installer.h

 // Copyright 2014 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_COMPONENT_UPDATER_SUPERVISED_USER_WHITELIST_INSTALLER_H_
 #define CHROME_BROWSER_COMPONENT_UPDATER_SUPERVISED_USER_WHITELIST_INSTALLER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 46 matching lines @@
   // shutdown or a crash).
   virtual void RegisterComponents() = 0;
 
   // Subscribes for notifications about available whitelists. Clients should
   // filter out the whitelists they are interested in via the |crx_id|
   // parameter.
   virtual void Subscribe(const WhitelistReadyCallback& callback) = 0;
 
   // Registers a new whitelist with the given |crx_id|.
   // The |client_id| should be a unique identifier for the client that is stable
-  // across restarts.
+  // across restarts. If it is empty, the registration will not be persisted in
+  // Local State.
   virtual void RegisterWhitelist(const std::string& client_id,
                                  const std::string& crx_id,
                                  const std::string& name) = 0;
 
   // Unregisters a whitelist.
   virtual void UnregisterWhitelist(const std::string& client_id,
                                    const std::string& crx_id) = 0;
 
  protected:
   // Triggers an update for a whitelist to be installed. Protected so it can be
   // called from the implementation subclass, and declared here so that the
   // OnDemandUpdater can friend this class and the implementation subclass can
   // live in an anonymous namespace.
   static void TriggerComponentUpdate(OnDemandUpdater* updater,
                                      const std::string& crx_id);
 };
 
 }  // namespace component_updater
 
 #endif  // CHROME_BROWSER_COMPONENT_UPDATER_SUPERVISED_USER_WHITELIST_INSTALLER_H_