Merge pull request #802 from mgreter/todo/issue_558

Add todo spec test for libsass issue 558

Author: mgreter

spec/libsass-todo-issues/issue_558/expected_output.css

@@ -0,0 +1,3 @@
+div {
+  foo: "yes";
+  bar: "no"; }

spec/libsass-todo-issues/issue_558/input.scss

@@ -0,0 +1,11 @@
+@function is_gold($c) {
+    @if ($c == gold) {
+        @return 'yes';
+    }
+    @return 'no';
+}
+
+div {
+    foo: is_gold(gold);
+    bar: is_gold(white);
+}