Adding app_shim executable on Windows.

chrome/app_shim/app_shim_win.gypi

+# 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.
+
+{
+  'targets': [
+    # This is the app shim on Windows. It is a small binary that simply runs
+    # Chrome, passing along any command-line arguments.
+    {
+      'target_name': 'app_shim',
+      'type': 'executable',
+      'dependencies': [
+        'launcher_support',
+        '../base/base.gyp:base',
+      ],
+      'sources': [
+        'win/app_shim.rc',
+        'win/app_shim_main.cc',
+      ],
+      'msvs_settings': {
+        'VCLinkerTool': {
+          'SubSystem': '2',     # Set /SUBSYSTEM:WINDOWS
+        },
+        'VCManifestTool': {
+          'AdditionalManifestFiles': [
+            'app_shim/win/app_shim.exe.manifest',
+          ],
+        },
+      },
+    },
+  ],  # targets
+}