Installer string cleaning following Chrome Frame removal.

chrome/installer/setup/setup_main.cc

 // 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.
 
 #include "chrome/installer/setup/setup_main.h"
 
 #include <windows.h>
 #include <msi.h>
 #include <shellapi.h>
 #include <shlobj.h>
@@ skipping 563 matching lines @@
             *status = installer::EXISTING_VERSION_LAUNCHED;
             base::FilePath chrome_exe =
                 install_path.Append(installer::kChromeExe);
             CommandLine cmd(chrome_exe);
             cmd.AppendSwitch(switches::kForceFirstRun);
             installer_state->WriteInstallerResult(*status, 0, NULL);
             VLOG(1) << "Launching existing system-level chrome instead.";
             base::LaunchProcess(cmd, base::LaunchOptions(), NULL);
           }
         } else {
-          // Display an error message for other products.
-          *status = installer::SYSTEM_LEVEL_INSTALL_EXISTS;
-          installer_state->WriteInstallerResult(
-              *status, IDS_INSTALL_SYSTEM_LEVEL_EXISTS_BASE, NULL);
+          // It's no longer possible for |product| to be anything other than
+          // Chrome.
+          NOTREACHED();
         }
         return false;
       }
     }
 
   } else {  // System-level install.
     // --ensure-google-update-present is supported for user-level only.
     // The flag is generic, but its primary use case involves App Host.
     if (installer_state->ensure_google_update_present()) {
       LOG(DFATAL) << "--" << installer::switches::kEnsureGoogleUpdatePresent
@@ skipping 1207 matching lines @@
     // Note that we allow the status installer::UNINSTALL_REQUIRES_REBOOT
     // to pass through, since this is only returned on uninstall which is
     // never invoked directly by Google Update.
     return_code = InstallUtil::GetInstallReturnCode(install_status);
   }
 
   VLOG(1) << "Installation complete, returning: " << return_code;
 
   return return_code;
 }