Fix official build in GN

components/data_reduction_proxy/core/common/version.gni

-# 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.
-
-# Runs the version processing script over the given template file to produce
-# an output file. This is used for generating various forms of files that
-# incorporate the product name and version.
-#
-# This template automatically includes VERSION,
-#
-# Parameters:
-#   source:
-#     File name of source template file to read.
-#
-#   output:
-#     File name of file to write.
-#
-#   visibility (optional)
-#
-# Example:
-#   process_version("myversion") {
-#     source = "myfile.h.in"
-#     output = "$target_gen_dir/myfile.h"
-#   }
-template("process_version") {
-  assert(defined(invoker.source), "Source must be defined for $target_name")
-  assert(defined(invoker.output), "Output must be defined for $target_name")
-
-  action(target_name) {
-    if (defined(invoker.visibility)) {
-      visibility = invoker.visibility
-    }
-    script = "//build/util/version.py"
-
-    version_path = "//chrome/VERSION"
-
-    inputs = [
-      version_path,
-      invoker.source,
-    ]
-
-    outputs = [
-      invoker.output,
-    ]
-
-    args = [
-      "-f",
-      rebase_path(version_path, root_build_dir),
-      rebase_path(invoker.source, root_build_dir),
-      rebase_path(invoker.output, root_build_dir),
-    ]
-  }
-}