Added asynchronous notification of readiness to the StatisticsProvider, and

chrome/browser/chromeos/system/mock_statistics_provider.h

Index: chrome/browser/chromeos/system/mock_statistics_provider.h
diff --git a/chrome/browser/chromeos/system/mock_statistics_provider.h b/chrome/browser/chromeos/system/mock_statistics_provider.h
index e0acd0a6ecf3a6d9fea08bcac21e753ef8f5e648..3b057e504a127d34679adb13855d9600ada32a61 100644
--- a/chrome/browser/chromeos/system/mock_statistics_provider.h
+++ b/chrome/browser/chromeos/system/mock_statistics_provider.h
@@ -21,6 +21,8 @@ class MockStatisticsProvider : public system::StatisticsProvider {
   MOCK_METHOD2(GetMachineStatistic, bool(const std::string& name,
                                          std::string* result));
 
+  MOCK_METHOD1(WhenReady, void(const base::Closure& callback));
+
  private:
   DISALLOW_COPY_AND_ASSIGN(MockStatisticsProvider);
 };