Apply gn format with 'sources' sorting to src/

sandbox/mac/BUILD.gn

 # 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.
 
 import("//build/config/mac/mac_sdk.gni")
 import("//testing/test.gni")
 
 component("sandbox") {
   sources = [
     "bootstrap_sandbox.cc",
@@ skipping 34 matching lines @@
 generate_stubs_script = "//tools/generate_stubs/generate_stubs.py"
 generate_stubs_header = "xpc_stubs_header.fragment"
 generate_stubs_sig_public = "xpc_stubs.sig"
 generate_stubs_sig_private = "xpc_private_stubs.sig"
 generate_stubs_project = "sandbox/mac"
 generate_stubs_output_stem = "xpc_stubs"
 
 action("generate_stubs") {
   script = generate_stubs_script
   sources = [
+    generate_stubs_sig_private,
     generate_stubs_sig_public,
-    generate_stubs_sig_private,
   ]
   inputs = [
     generate_stubs_header,
   ]
   outputs = [
     "$target_gen_dir/$generate_stubs_output_stem.cc",
     "$target_gen_dir/$generate_stubs_output_stem.h",
   ]
   args = [
     "-i",
@@ skipping 27 matching lines @@
     "Foundation.framework",
   ]
 
   deps = [
     ":sandbox",
     "//base",
     "//base/test:run_all_unittests",
     "//testing/gtest",
   ]
 }