[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/bindings/declarative_event.cc

 // Copyright 2017 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.
 
-#include "extensions/renderer/declarative_event.h"
+#include "extensions/renderer/bindings/declarative_event.h"
 
 #include <algorithm>
 #include <memory>
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/values.h"
-#include "extensions/renderer/api_event_listeners.h"
-#include "extensions/renderer/api_request_handler.h"
-#include "extensions/renderer/api_signature.h"
-#include "extensions/renderer/api_type_reference_map.h"
-#include "extensions/renderer/argument_spec.h"
+#include "extensions/renderer/bindings/api_event_listeners.h"
+#include "extensions/renderer/bindings/api_request_handler.h"
+#include "extensions/renderer/bindings/api_signature.h"
+#include "extensions/renderer/bindings/api_type_reference_map.h"
+#include "extensions/renderer/bindings/argument_spec.h"
 #include "gin/object_template_builder.h"
 #include "gin/per_context_data.h"
 
 namespace extensions {
 
 namespace {
 
 // Builds an ArgumentSpec that accepts the given |choices| as references.
 std::unique_ptr<ArgumentSpec> BuildChoicesSpec(
     const std::vector<std::string>& choices_list) {
@@ skipping 169 matching lines @@
     arguments->ThrowTypeError("Invalid invocation");
     return;
   }
 
   request_handler_->StartRequest(
       context, request_name, std::move(converted_arguments), callback,
       v8::Local<v8::Function>(), binding::RequestThread::UI);
 }
 
 }  // namespace extensions