Fix chrome target in Windows GN build.

extensions/shell/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.
 
 # Technically, this directory should not depend on files from src/chrome, but
 # that's where the VERSION file is. This  should probably all be moved to
 # src/build.
 import("//chrome/version.gni")
 import("//tools/grit/grit_rule.gni")
 
@@ skipping 145 matching lines @@
   executable("app_shell") {
     # testonly because :app_shell_lib is testonly. See :app_shell_lib comment.
     testonly = true
     sources = [
       "app/shell_main.cc",
     ]
     deps = [
       ":app_shell_lib",
       "//extensions:shell_and_test_pak",
     ]
+
+    if (is_win) {
+      configs += [ "//build/config/win:windowed" ]
+      configs -= [ "//build/config/win:console" ]
+    }
   }
 }
 
 process_version("version_header") {
   source = "common/version.h.in"
   output = "$target_gen_dir/common/version.h"
 }