[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/bindings/api_bindings_system.h

 // Copyright 2016 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 EXTENSIONS_RENDERER_API_BINDINGS_SYSTEM_H_
-#define EXTENSIONS_RENDERER_API_BINDINGS_SYSTEM_H_
+#ifndef EXTENSIONS_RENDERER_BINDINGS_API_BINDINGS_SYSTEM_H_
+#define EXTENSIONS_RENDERER_BINDINGS_API_BINDINGS_SYSTEM_H_
 
 #include <map>
 #include <memory>
 #include <string>
 
 #include "base/callback.h"
 #include "base/macros.h"
-#include "extensions/renderer/api_binding.h"
-#include "extensions/renderer/api_binding_types.h"
-#include "extensions/renderer/api_event_handler.h"
-#include "extensions/renderer/api_last_error.h"
-#include "extensions/renderer/api_request_handler.h"
-#include "extensions/renderer/api_type_reference_map.h"
+#include "extensions/renderer/bindings/api_binding.h"
+#include "extensions/renderer/bindings/api_binding_types.h"
+#include "extensions/renderer/bindings/api_event_handler.h"
+#include "extensions/renderer/bindings/api_last_error.h"
+#include "extensions/renderer/bindings/api_request_handler.h"
+#include "extensions/renderer/bindings/api_type_reference_map.h"
 
 namespace base {
 class DictionaryValue;
 class ListValue;
 }
 
 namespace extensions {
 class APIBindingHooks;
 
 // A class encompassing the necessary pieces to construct the JS entry points
@@ skipping 105 matching lines @@
   // API. Curried in for testing purposes so we can use fake APIs.
   GetAPISchemaMethod get_api_schema_;
 
   APIBinding::AvailabilityCallback is_available_;
 
   DISALLOW_COPY_AND_ASSIGN(APIBindingsSystem);
 };
 
 }  // namespace
 
-#endif  // EXTENSIONS_RENDERER_API_BINDINGS_SYSTEM_H_
+#endif  // EXTENSIONS_RENDERER_BINDINGS_API_BINDINGS_SYSTEM_H_