[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/native_extension_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_NATIVE_EXTENSION_BINDINGS_SYSTEM_H_
 #define EXTENSIONS_RENDERER_NATIVE_EXTENSION_BINDINGS_SYSTEM_H_
 
 #include <memory>
 #include <string>
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
-#include "extensions/renderer/api_binding_types.h"
-#include "extensions/renderer/api_bindings_system.h"
-#include "extensions/renderer/event_emitter.h"
+#include "extensions/renderer/bindings/api_binding_types.h"
+#include "extensions/renderer/bindings/api_bindings_system.h"
+#include "extensions/renderer/bindings/event_emitter.h"
 #include "extensions/renderer/extension_bindings_system.h"
 #include "v8/include/v8.h"
 
 struct ExtensionHostMsg_Request_Params;
 
 namespace extensions {
 class ScriptContext;
 
 // The implementation of the Bindings System for extensions code with native
 // implementations (rather than JS hooks). Handles permission/availability
@@ skipping 86 matching lines @@
   v8::Eternal<v8::FunctionTemplate> get_internal_api_;
 
   base::WeakPtrFactory<NativeExtensionBindingsSystem> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeExtensionBindingsSystem);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_NATIVE_EXTENSION_BINDINGS_SYSTEM_H_