Starting work on full GN build

build/config/chrome_build.gni

-# Copyright 2015 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.
-
-declare_args() {
-  # Selects the desired build flavor. Official builds get additional
-  # processing to prepare for release. Normally you will want to develop and
-  # test with this flag off.
-  is_official_build = false
-
-  # Select the desired branding flavor. False means normal Chromium branding,
-  # true means official Google Chrome branding (requires extra Google-internal
-  # resources).
-  is_chrome_branded = false
-
-  # Break chrome.dll into multple pieces based on process type. Only available
-  # on Windows.
-  is_multi_dll_chrome = is_win && !is_component_build
-}