[Extensions Bindings] Add a bridge to use current custom bindings

extensions/renderer/api_binding_bridge.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_BINDING_BRIDGE_H_
+#define EXTENSIONS_RENDERER_API_BINDING_BRIDGE_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "extensions/renderer/api_binding_types.h"
+#include "gin/wrappable.h"
+#include "v8/include/v8.h"
+
+namespace extensions {
+
+// An object that serves as a bridge between the current JS-centric bindings and
+// the new native bindings system. This basically needs to conform to the public
+// methods of the Binding prototype in binding.js.
+class APIBindingBridge final : public gin::Wrappable<APIBindingBridge> {
+ public:
+  APIBindingBridge(v8::Local<v8::Context> context,
+                   v8::Local<v8::Value> api_object,
+                   v8::Local<v8::Value> js_hook_interface,
+                   const std::string& extension_id,
+                   const std::string& context_type,
+                   const binding::RunJSFunction& run_js);
+  ~APIBindingBridge() override;
+
+  static gin::WrapperInfo kWrapperInfo;
+
+  // gin::Wrappable:
+  gin::ObjectTemplateBuilder GetObjectTemplateBuilder(
+      v8::Isolate* isolate) final;
+
+ private:
+  // Runs the given function and registers custom hooks.
+  // The function takes three arguments: an object,
+  // {
+  //   apiFunctions: <JSHookInterface> (see api_bindings_hooks.cc),
+  //   compiledApi: <the API object>
+  // }
+  // as well as a string for the extension ID and a string for the context type.
+  // This should register any hooks that the JS needs for the given API.
+  void RegisterCustomHook(v8::Isolate* isolate,
+                          v8::Local<v8::Function> function);
+
+  // The id of the extension that owns the context this belongs to.
+  std::string extension_id_;
+
+  // The type of context this belongs to.
+  std::string context_type_;
+
+  // A function to run JS safely.
+  binding::RunJSFunction run_js_;
+
+  DISALLOW_COPY_AND_ASSIGN(APIBindingBridge);
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_RENDERER_API_BINDING_BRIDGE_H_