Refactor SetOmahaExperimentLabel out of gcpai and into install_util.

chrome/installer/util/google_update_settings.h

 // 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_INSTALLER_UTIL_GOOGLE_UPDATE_SETTINGS_H_
 #define CHROME_INSTALLER_UTIL_GOOGLE_UPDATE_SETTINGS_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 230 matching lines @@
 
   // Returns product data for Google Update.  (Equivalent to calling
   // GetUpdateDetailForAppGuid with the app guid for Google Update itself.)
   static bool GetUpdateDetailForGoogleUpdate(bool system_install,
                                              ProductData* data);
 
   // Returns product data for the current product. (Equivalent to calling
   // GetUpdateDetailForApp with the app guid stored in BrowserDistribution.)
   static bool GetUpdateDetail(bool system_install, ProductData* data);
 
+  // Sets |experiment_labels| as the Omaha experiment_labels value in the
+  // ClientState key for this Chrome product, if appropriate. If
+  // |experiment_labels| is empty, this will delete the value instead. This will
+  // return true if the label was successfully set (or deleted), false otherwise
+  // (even if the label does not need to be set for this particular distribution
+  // type).
+  static bool SetExperimentLabels(bool system_install,
+                                  const string16& experiment_labels);
+
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(GoogleUpdateSettings);
 };
 
 #endif  // CHROME_INSTALLER_UTIL_GOOGLE_UPDATE_SETTINGS_H_