Add a snapshot of flutter/engine/src/build to our sdk

build/util/version.gypi

+# Copyright 2014 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.
+
+{
+  'variables': {
+    'variables': {
+      'version_py_path': '<(DEPTH)/build/util/version.py',
+      'version_path': '<(DEPTH)/chrome/VERSION',
+      'lastchange_path': '<(DEPTH)/build/util/LASTCHANGE',
+    },
+    'version_py_path': '<(version_py_path)',
+    'version_path': '<(version_path)',
+    'lastchange_path': '<(lastchange_path)',
+    'version_full':
+        '<!(python <(version_py_path) -f <(version_path) -t "@MAJOR@.@MINOR@.@BUILD@.@PATCH@")',
+    'version_mac_dylib':
+        '<!(python <(version_py_path) -f <(version_path) -t "@BUILD@.@PATCH_HI@.@PATCH_LO@" -e "PATCH_HI=int(PATCH)/256" -e "PATCH_LO=int(PATCH)%256")',
+  },  # variables
+}