Lo-Fi snackbar should only be shown for the first q=low response of a page

components/data_reduction_proxy/core/common/lofi_ui_service.h

Index: components/data_reduction_proxy/core/common/lofi_ui_service.h
diff --git a/components/data_reduction_proxy/core/common/lofi_ui_service.h b/components/data_reduction_proxy/core/common/lofi_ui_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..656dab4de9bd51c2e39f9e14a1f06a79c4a6f3f2
--- /dev/null
+++ b/components/data_reduction_proxy/core/common/lofi_ui_service.h
@@ -0,0 +1,28 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_LOFI_UI_SERVICE_H_
+#define COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_LOFI_UI_SERVICE_H_
+
+#include "base/macros.h"
+
+namespace net {
+class URLRequest;
+}
+
+namespace data_reduction_proxy {
+
+// Passes notifications to the UI thread that a Lo-Fi response has been
+// received. These notifications may be used to show Lo-Fi UI.
+class LoFiUIService {
+ public:
+  virtual ~LoFiUIService() {}
+
+  // Notifies the UI thread that |request| has a Lo-Fi response.
+  virtual void OnLoFiReponseReceived(const net::URLRequest& request) = 0;
+};
+
+}  // namespace data_reduction_proxy
+
+#endif  // COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_LOFI_UI_SERVICE_H_