Add Keys() function to ServiceWorkerCache.

content/browser/service_worker/service_worker_cache.h

Index: content/browser/service_worker/service_worker_cache.h
diff --git a/content/browser/service_worker/service_worker_cache.h b/content/browser/service_worker/service_worker_cache.h
index 42393a29e1ea10cfff90b9b8babb2f788bd89d3e..29658473568e27cef2bd7c791fcc72337836b890 100644
--- a/content/browser/service_worker/service_worker_cache.h
+++ b/content/browser/service_worker/service_worker_cache.h
@@ -46,6 +46,10 @@ class CONTENT_EXPORT ServiceWorkerCache {
                               scoped_ptr<ServiceWorkerResponse>,
                               scoped_ptr<storage::BlobDataHandle>)>
       ResponseCallback;
+  typedef std::vector<ServiceWorkerFetchRequest> Requests;
+  typedef base::Callback<void(ErrorType, scoped_ptr<Requests>)>
+      RequestsCallback;
+
   static scoped_ptr<ServiceWorkerCache> CreateMemoryCache(
       net::URLRequestContext* request_context,
       base::WeakPtr<storage::BlobStorageContext> blob_context);
@@ -80,6 +84,11 @@ class CONTENT_EXPORT ServiceWorkerCache {
   void Delete(ServiceWorkerFetchRequest* request,
               const ErrorCallback& callback);
 
+  // TODO(jkarlin): Have keys take an optional ServiceWorkerFetchRequest.
+  // Returns ErrorTypeOK and a vector of requests if there are no errors. The
+  // callback will always be called.
+  void Keys(const RequestsCallback& callback);
+
   // Call to determine if CreateBackend must be called.
   bool HasCreatedBackend() const;
 
@@ -87,6 +96,8 @@ class CONTENT_EXPORT ServiceWorkerCache {
     backend_ = backend.Pass();
   }
 
+  disk_cache::Backend* backend() const { return backend_.get(); }
+
   base::WeakPtr<ServiceWorkerCache> AsWeakPtr();
 
  private: