Make symlink.py always updates the symlink timestamp

build/symlink.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.
 
 # Creates a symlink.
 # Args:
 #   source: Path to link to.
 #   output: Where to create the symlink.
 template("symlink") {
   action(target_name) {
@@ skipping 35 matching lines @@
 #     executable("foo") { ... }
 #   } else if (current_toolchain == default_toolchain) {
 #     binary_symlink("foo") {
 #       binary_label = ":foo($host_toolchain)"
 #     }
 #   }
 template("binary_symlink") {
   symlink(target_name) {
     forward_variables_from(invoker,
                            [
-                             "output",
                              "testonly",
                              "visibility",
                            ])
     deps = [
       invoker.binary_label,
     ]
 
     _out_dir = get_label_info(invoker.binary_label, "root_out_dir")
     if (defined(invoker.binary_output_name)) {
       _name = invoker.binary_output_name
     } else {
       _name = get_label_info(invoker.binary_label, "name")
     }
     source = "$_out_dir/$_name"
 
     _output_name = _name
     if (defined(invoker.output_name)) {
       _output_name = invoker.output_name
     }
     output = "$root_out_dir/$_output_name"
   }
 }