Invoke setup.exe to reenable updates when the update bubble is clicked.

chrome/installer/util/google_update_util.h

Index: chrome/installer/util/google_update_util.h
diff --git a/chrome/installer/util/google_update_util.h b/chrome/installer/util/google_update_util.h
index 8ef2b9a7539c9e09f5f7c00060a1a6efb1b1c916..7944e0f120cc161e25e442cb9c373b3c2c79a0a8 100644
--- a/chrome/installer/util/google_update_util.h
+++ b/chrome/installer/util/google_update_util.h
@@ -22,6 +22,11 @@ bool EnsureUserLevelGoogleUpdatePresent();
 // Returns false if Google Update could not be executed, or times out.
 bool UninstallGoogleUpdate(bool system_install);
 
+// Run setup.exe to attempt to reenable updates for for Chrome while elevating
+// if needed. Setup.exe will call into
+// GoogleUpdateSettings::ReenableAutoupdatesForApp() to do the work.
+bool ElevateIfNeededToReenableUpdates();
+
 // Returns the value corresponding to |key| in untrusted data passed from
 // Google Update.  Returns an empty string if |key| is absent or if its value
 // contains non-printable characters.