[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/api_binding_types.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_TYPES_H_
-#define EXTENSIONS_RENDERER_API_BINDING_TYPES_H_
-
-#include <memory>
-#include <vector>
-
-#include "base/callback.h"
-#include "v8/include/v8.h"
-
-namespace extensions {
-namespace binding {
-
-// A value indicating an event has no maximum listener count.
-extern const int kNoListenerMax;
-
-// Types of changes for event listener registration.
-enum class EventListenersChanged {
-  HAS_LISTENERS,  // The event had no listeners, and now does.
-  NO_LISTENERS,   // The event had listeners, and now does not.
-};
-
-// The browser thread that the request should be sent to.
-enum class RequestThread {
-  UI,
-  IO,
-};
-
-// A callback to execute the given v8::Function with the provided context and
-// arguments.
-using RunJSFunction = base::Callback<void(v8::Local<v8::Function>,
-                                          v8::Local<v8::Context>,
-                                          int argc,
-                                          v8::Local<v8::Value>[])>;
-
-// A callback to execute the given v8::Function synchronously and return the
-// result. Note that script can be suspended, so you need to be certain that
-// it is not before expected a synchronous result. We use a Global instead of a
-// Local because certain implementations need to create a persistent handle in
-// order to prevent immediate destruction of the locals.
-// TODO(devlin): if we could, using Local here with an EscapableHandleScope
-// would be preferable.
-using RunJSFunctionSync =
-    base::Callback<v8::Global<v8::Value>(v8::Local<v8::Function>,
-                                         v8::Local<v8::Context>,
-                                         int argc,
-                                         v8::Local<v8::Value>[])>;
-
-}  // namespace binding
-}  // namespace extensions
-
-#endif  // EXTENSIONS_RENDERER_API_BINDING_TYPES_H_