Initial gyp files for SDL

third_party/libsdl/sdl.gypi

+# Copyright 2015 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'targets': [
+    {
+      'target_name': 'sdl',
+      'product_name': 'sdl',
+      'type': 'shared_library',
+      'include_dirs': [
+        '<(base_dir)/<(skia_os)',
+        '<(src_dir)/include',
+      ],
+      'includes': [
+        'sdl_sources.gypi',
+      ],
+      'sources': [
+        '<@(sdl_sources)',

[mtklein, 2015/10/28 21:12:15]

Is this the same deal?  Why can't we just write out the sources here?

[joshualitt, 2015/10/29 13:51:39]

see below.

+      ],
+      'direct_dependent_settings': {
+        'include_dirs': [
+          '<(src_dir)/include',
+        ]
+      },
+      'cflags': [
+        '-g',
+        '-Wall'

[mtklein, 2015/10/28 21:12:15]

Do we really care about warnings in SDL?  I'd suggest -w.

[joshualitt, 2015/10/29 13:51:39]

Acknowledged.

+      ],
+      'conditions': [
+        ['skia_os == "linux"', {
+          'includes': [
+            'linux/sdl_linux.gypi',

[mtklein, 2015/10/28 21:12:15]

Is this just a factoring preference, or is something making us use a .gypi here?

[joshualitt, 2015/10/29 13:51:39]

I prefer smaller gyps which show the core logic, and then dummy gypis with lists
of files.  It just makes it easier for me to work with flatter gyps, as opposed
to heavily nested gyps with long lists of files.

We also do this with the gpu files, so its not unheard of in our codebase.

I'd prefer to leave the separate gpyis for now.  Once I have rolled out on
mac/windows/ios/android, we can revisit.

+          ]
+        }],
+      ],
+    },
+  ],
+}