Update from chromium https://crrev.com/302282

build/go/go.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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.
 
 """
 This script invokes the go build tool.
 Must be called as follows:
 python go.py <go-binary> <build directory> <output file> <src directory>
 <CGO_CFLAGS> <CGO_LDFLAGS> <go-binary options>
@@ skipping 17 matching lines @@
   parser.add_argument('cgo_ldflags')
   parser.add_argument('go_option', nargs='*')
   args = parser.parse_args()
   go_binary = args.go_binary
   build_dir = args.build_directory
   out_file = os.path.abspath(args.output_file)
   # The src directory specified is relative. We need this as an absolute path.
   src_root = os.path.abspath(args.src_root)
   # GOPATH must be absolute, and point to one directory up from |src_Root|
   go_path = os.path.abspath(os.path.join(src_root, ".."))
-  # GOPATH also includes any third_party/go libraries that have been imported
-  go_path += ":" +  os.path.abspath(os.path.join(src_root, "third_party/go"))
   go_options = args.go_option
   try:
     shutil.rmtree(build_dir, True)
     os.mkdir(build_dir)
   except:
     pass
   old_directory = os.getcwd()
   os.chdir(build_dir)
   os.environ["GOPATH"] = go_path
   os.environ["CGO_CFLAGS"] = args.cgo_cflags
   os.environ["CGO_LDFLAGS"] = args.cgo_ldflags
   os.system("%s %s" % (go_binary, " ".join(go_options)))
   out_files = [ f for f in os.listdir(".") if os.path.isfile(f)]
   if (len(out_files) > 0):
     shutil.move(out_files[0], out_file)
   os.chdir(old_directory)
   try:
     shutil.rmtree(build_dir, True)
   except:
     pass
 
 if __name__ == '__main__':
   sys.exit(main())