[ServiceWorkerCacheStorage] Add support for new Open method.

content/browser/service_worker/service_worker_cache_storage.h

Index: content/browser/service_worker/service_worker_cache_storage.h
diff --git a/content/browser/service_worker/service_worker_cache_storage.h b/content/browser/service_worker/service_worker_cache_storage.h
index cec6389c9323123316ae209e3c2ec6c8f031b2af..93989250e1971cea327df37cb11725ea582bbcac 100644
--- a/content/browser/service_worker/service_worker_cache_storage.h
+++ b/content/browser/service_worker/service_worker_cache_storage.h
@@ -59,16 +59,21 @@ class CONTENT_EXPORT ServiceWorkerCacheStorage {
   virtual ~ServiceWorkerCacheStorage();
 
   // Create a ServiceWorkerCache if it doesn't already exist and call the
-  // callback with the cache's id. If it already
+  // callback with the cache. If it already
   // exists the callback is called with CACHE_STORAGE_ERROR_EXISTS.
   void CreateCache(const std::string& cache_name,
                    const CacheAndErrorCallback& callback);
 
-  // Get the cache id for the given key. If not found returns
+  // Get the cache for the given key. If not found returns
   // CACHE_STORAGE_ERROR_NOT_FOUND.
   void GetCache(const std::string& cache_name,
                 const CacheAndErrorCallback& callback);
 
+  // Get the cache for the given key. If the cache is not found it is
+  // created.
+  void OpenCache(const std::string& cache_name,
+                 const CacheAndErrorCallback& callback);
+
   // Calls the callback with whether or not the cache exists.
   void HasCache(const std::string& cache_name,
                 const BoolAndErrorCallback& callback);