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

build/symlink.py

+#!/usr/bin/env python
+# Copyright (c) 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.
+"""Make a symlink and optionally touch a file (to handle dependencies)."""
+import errno
+import optparse
+import os.path
+import shutil
+import sys
+def Main(argv):
+  parser = optparse.OptionParser()
+  parser.add_option('-f', '--force', action='store_true')
+  parser.add_option('--touch')
+  options, args = parser.parse_args(argv[1:])
+  if len(args) < 2:
+    parser.error('at least two arguments required.')
+  target = args[-1]
+  sources = args[:-1]
+  for s in sources:
+    t = os.path.join(target, os.path.basename(s))
+    if len(sources) == 1 and not os.path.isdir(target):
+      t = target
+    try:
+      os.symlink(s, t)
+    except OSError, e:
+      if e.errno == errno.EEXIST and options.force:
+        if os.path.isdir(t):
+          shutil.rmtree(t, ignore_errors=True)
+        else:
+          os.remove(t)
+        os.symlink(s, t)
+      else:
+        raise
+  if options.touch:
+    with open(options.touch, 'w') as f:
+      pass
+if __name__ == '__main__':
+  sys.exit(Main(sys.argv))