Get main frame and subframe AppCache loads to work.

content/browser/appcache/mock_appcache_storage.cc

Index: content/browser/appcache/mock_appcache_storage.cc
diff --git a/content/browser/appcache/mock_appcache_storage.cc b/content/browser/appcache/mock_appcache_storage.cc
index a5c5382c639c948ecb11a0190c25eff3db155cca..1bd3bed59aa8b8583d5e57d900a9e22215780e87 100644
--- a/content/browser/appcache/mock_appcache_storage.cc
+++ b/content/browser/appcache/mock_appcache_storage.cc
@@ -201,6 +201,10 @@ void MockAppCacheStorage::DeleteResponses(
   }
 }
 
+bool MockAppCacheStorage::IsInitialized() {
+  return false;
+}
+
 void MockAppCacheStorage::ProcessGetAllInfo(
     scoped_refptr<DelegateReference> delegate_ref) {
   if (delegate_ref->delegate)