Move extensions bindings code out of //chrome

chrome/renderer/extensions/id_generator_custom_bindings.cc

-// Copyright 2013 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 "chrome/renderer/extensions/id_generator_custom_bindings.h"
-
-#include "base/bind.h"
-#include "grit/renderer_resources.h"
-#include "v8/include/v8.h"
-
-namespace extensions {
-
-IdGeneratorCustomBindings::IdGeneratorCustomBindings(Dispatcher* dispatcher,
-                                                     ChromeV8Context* context)
-    : ChromeV8Extension(dispatcher, context) {
-  RouteFunction("GetNextId", base::Bind(&IdGeneratorCustomBindings::GetNextId,
-                                        base::Unretained(this)));
-}
-
-void IdGeneratorCustomBindings::GetNextId(
-    const v8::FunctionCallbackInfo<v8::Value>& args) {
-  static int32_t next_id = 0;
-  ++next_id;
-  // Make sure 0 is never returned because some APIs (particularly WebRequest)
-  // have special meaning for 0 IDs.
-  if (next_id == 0)
-    next_id = 1;
-  args.GetReturnValue().Set(next_id);
-}
-
-}  // namespace extensions