Modify UpdateLibrary to use async RequestUpdateCheck call

chrome/browser/chromeos/cros/update_library.h

Index: chrome/browser/chromeos/cros/update_library.h
diff --git a/chrome/browser/chromeos/cros/update_library.h b/chrome/browser/chromeos/cros/update_library.h
index 0ad23c03c06e9394875825b12ab5d68efe4eaee0..a5c97994a8a5d0b6b9c64d6168647ea7f16ccab6 100644
--- a/chrome/browser/chromeos/cros/update_library.h
+++ b/chrome/browser/chromeos/cros/update_library.h
@@ -62,8 +62,9 @@ class UpdateLibrary {
   virtual void AddObserver(Observer* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
 
-  // Initiates update check and returns true if check was initiated.
-  virtual bool CheckForUpdate() = 0;
+  // Request an update check and call |callback| when the request has completed.

[altimofeev, 2011/03/10 08:27:34]

nit: Requests, calls (third person singular)

[stevenjb, 2011/03/10 17:28:50]

Done.

+  virtual void RequestUpdateCheck(chromeos::UpdateCallback callback,
+                                  void* user_data) = 0;
 
   // Reboots if update has been performed.
   virtual bool RebootAfterUpdate() = 0;