Add installer::SetupSingleton.

chrome/installer/setup/setup_main.cc

Index: chrome/installer/setup/setup_main.cc
diff --git a/chrome/installer/setup/setup_main.cc b/chrome/installer/setup/setup_main.cc
index 7860d34cf4ff0dd1a0685d5849c7ea50597d6114..cab865250e7e8d312c68f071b29e06682c3b9158 100644
--- a/chrome/installer/setup/setup_main.cc
+++ b/chrome/installer/setup/setup_main.cc
@@ -51,6 +51,7 @@
 #include "chrome/installer/setup/installer_crash_reporting.h"
 #include "chrome/installer/setup/installer_metrics.h"
 #include "chrome/installer/setup/setup_constants.h"
+#include "chrome/installer/setup/setup_singleton.h"
 #include "chrome/installer/setup/setup_util.h"
 #include "chrome/installer/setup/uninstall.h"
 #include "chrome/installer/util/browser_distribution.h"
@@ -395,6 +396,8 @@ void AddExistingMultiInstalls(const InstallationState& original_state,
 installer::InstallStatus RenameChromeExecutables(
     const InstallationState& original_state,
     InstallerState* installer_state) {
+  installer::SetupSingleton setup_singleton(*installer_state);
+
   // See what products are already installed in multi mode.  When we do the
   // rename for multi installs, we must update all installations since they
   // share the binaries.
@@ -1843,6 +1846,8 @@ int WINAPI wWinMain(HINSTANCE instance, HINSTANCE prev_instance,
     }
   }
 
+  installer::SetupSingleton setup_singleton(installer_state);
+
   UninstallMultiChromeFrameIfPresent(cmd_line, prefs,
                                      &original_state, &installer_state);