Auto merge of #9333 - servo:list-properties, r=larsbergstrom

Add a script to list all CSS properties parsed by Servo.

I’ve been asked for that list by two different people this week :)

r? @larsbergstrom

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components/style/list_properties.py

@@ -0,0 +1,24 @@
+#!/usr/bin/env python
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import os.path
+import sys
+import json
+
+style = os.path.dirname(__file__)
+sys.path.insert(0, os.path.join(style, "Mako-0.9.1.zip"))
+from mako.template import Template
+
+template = Template(filename=os.path.join(style, "properties.mako.rs"), input_encoding='utf8')
+template.render()
+properties = dict(
+    (p.name, {
+        "flag": p.experimental,
+        "shorthand": hasattr(p, "sub_properties")
+    })
+    for p in template.module.LONGHANDS + template.module.SHORTHANDS
+)
+print(json.dumps(properties, indent=4))