Add a counter to calculate the total size of site data.

chrome/browser/browsing_data/mock_browsing_data_appcache_helper.h

Index: chrome/browser/browsing_data/mock_browsing_data_appcache_helper.h
diff --git a/chrome/browser/browsing_data/mock_browsing_data_appcache_helper.h b/chrome/browser/browsing_data/mock_browsing_data_appcache_helper.h
index 4e2a71ce4c060408dae7cfeebded19e1c58f2296..30631bebb026927f7ad684a8e300ffb4f151507e 100644
--- a/chrome/browser/browsing_data/mock_browsing_data_appcache_helper.h
+++ b/chrome/browser/browsing_data/mock_browsing_data_appcache_helper.h
@@ -18,11 +18,19 @@ class MockBrowsingDataAppCacheHelper
   void StartFetching(const FetchCallback& completion_callback) override;
   void DeleteAppCacheGroup(const GURL& manifest_url) override;
 
+  // Adds AppCache samples.
+  void AddAppCacheSamples();
+
+  // Notifies the callback.
+  void Notify();
+
  private:
   ~MockBrowsingDataAppCacheHelper() override;
 
   FetchCallback completion_callback_;
 
+  scoped_refptr<content::AppCacheInfoCollection> response_;
+
   DISALLOW_COPY_AND_ASSIGN(MockBrowsingDataAppCacheHelper);
 };