[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/api_binding_hooks.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_HOOKS_H_
-#define EXTENSIONS_RENDERER_API_BINDING_HOOKS_H_
-
-#include <memory>
-#include <string>
-
-#include "base/macros.h"
-#include "extensions/renderer/api_binding_types.h"
-#include "v8/include/v8.h"
-
-namespace extensions {
-class APIBindingHooksDelegate;
-class APITypeReferenceMap;
-class APISignature;
-
-// A class to register custom hooks for given API calls that need different
-// handling. An instance exists for a single API, but can be used across
-// multiple contexts (but only on the same thread).
-// TODO(devlin): We have both C++ and JS custom bindings, but this only allows
-// for registration of C++ handlers. Add JS support.
-class APIBindingHooks {
- public:
-  // The result of checking for hooks to handle a request.
-  struct RequestResult {
-    enum ResultCode {
-      HANDLED,             // A custom hook handled the request.
-      ARGUMENTS_UPDATED,   // The arguments were updated post-validation.
-      THROWN,              // An exception was thrown during parsing or
-                           // handling.
-      INVALID_INVOCATION,  // The request was called with invalid arguments.
-                           // |error| will contain the invocation error.
-      NOT_HANDLED,         // The request was not handled.
-    };
-
-    explicit RequestResult(ResultCode code);
-    RequestResult(ResultCode code, v8::Local<v8::Function> custom_callback);
-    RequestResult(std::string invocation_error);
-    RequestResult(const RequestResult& other);
-    ~RequestResult();
-
-    ResultCode code;
-    v8::Local<v8::Function> custom_callback;
-    v8::Local<v8::Value> return_value;  // Only valid if code == HANDLED.
-    std::string error;
-  };
-
-  APIBindingHooks(const std::string& api_name,
-                  const binding::RunJSFunctionSync& run_js);
-  ~APIBindingHooks();
-
-  // Looks for any custom hooks associated with the given request, and, if any
-  // are found, runs them. Returns the result of running the hooks, if any.
-  RequestResult RunHooks(const std::string& method_name,
-                         v8::Local<v8::Context> context,
-                         const APISignature* signature,
-                         std::vector<v8::Local<v8::Value>>* arguments,
-                         const APITypeReferenceMap& type_refs);
-
-  // Returns a JS interface that can be used to register hooks.
-  v8::Local<v8::Object> GetJSHookInterface(v8::Local<v8::Context> context);
-
-  // Gets the custom-set JS callback for the given method, if one exists.
-  v8::Local<v8::Function> GetCustomJSCallback(const std::string& method_name,
-                                              v8::Local<v8::Context> context);
-
-  // Creates a new JS event for the given |event_name|, if a custom event is
-  // provided. Returns true if an event was created.
-  bool CreateCustomEvent(v8::Local<v8::Context> context,
-                         const std::string& event_name,
-                         v8::Local<v8::Value>* event_out);
-
-  // Performs any extra initialization on the template.
-  void InitializeTemplate(v8::Isolate* isolate,
-                          v8::Local<v8::ObjectTemplate> object_template,
-                          const APITypeReferenceMap& type_refs);
-
-  void SetDelegate(std::unique_ptr<APIBindingHooksDelegate> delegate);
-
- private:
-  // Updates the |arguments| by running |function| and settings arguments to the
-  // returned result.
-  bool UpdateArguments(v8::Local<v8::Function> function,
-                       v8::Local<v8::Context> context,
-                       std::vector<v8::Local<v8::Value>>* arguments);
-
-  // The name of the associated API.
-  std::string api_name_;
-
-  // We use synchronous JS execution here because at every point we execute JS,
-  // it's in direct response to JS calling in. There should be no reason that
-  // script is disabled.
-  binding::RunJSFunctionSync run_js_;
-
-  std::unique_ptr<APIBindingHooksDelegate> delegate_;
-
-  DISALLOW_COPY_AND_ASSIGN(APIBindingHooks);
-};
-
-}  // namespace extensions
-
-#endif  // EXTENSIONS_RENDERER_API_BINDING_HOOKS_H_