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_win',

[grt (UTC plus 2), 2014/10/30 17:04:56]

it seems that this does something completely different than the "app_shim" for
OSX in this directory. overloading the term like this seems like a mistake. is
there a more appropriate name/location for this component?

[Matt Giuca, 2014/10/30 21:16:35]

It's the same concept: a small shim to run an app because the OS won't let us
run Chrome directly, for whatever reason.

The differences are:
- The Mac one needs to stay resident for the lifetime of the app, whereas the
Windows one can quit once the app is launched.
- The Mac one is used to give the app a dock icon and it's own presence in the
OS menu, as well as to provide a target for file associations. The Windows one
is just to provide a target for for associations.

Those differences aren't enough to justify using a different name. They do
almost exactly the same thing and are both used for the same purpose.

[grt (UTC plus 2), 2014/10/31 14:29:59]

Ah, I misunderstood what the Mac one does. Thanks for clarifying. In that case,
why not put both in app_shim.gypi with platform-specific conditionals inside for
each target?

[Matt Giuca, 2014/11/04 04:38:17]

Discussed with Jack (owner of app_shim.gypi); the files do not share any code
and making them work in the same file means extra complexity (checking for OS
and excluding code), because there are variables required by the Mac one that
aren't available on Windows.

Jack: "I'd rather two readable .gypi files than one unreadable one."

He's going to rename his file to app_shim_mac.gypi so there is no confusion.

[grt (UTC plus 2), 2014/11/04 14:04:52]

SGTM, thanks.

+      'type': 'executable',
+      'include_dirs': [
+        '../..',

[grt (UTC plus 2), 2014/10/30 17:04:56]

is this necessary?

[Matt Giuca, 2014/11/04 04:38:17]

Apparently not. Deleted.

+      ],
+      'dependencies': [
+        'launcher_support',
+        '../base/base.gyp:base',
+      ],
+      'sources': [
+        'app_shim_win.cc',
+        'app_shim_win.rc',
+      ],
+      'msvs_settings': {
+        'VCLinkerTool': {
+          'SubSystem': '2',     # Set /SUBSYSTEM:WINDOWS
+        },
+      },
+    },
+  ],  # targets
+}