Better decimal support (For ABCs with minor version 17)

libsrc/ffdec_lib/testdata/decimal/src/Toplevel.as

@@ -0,0 +1,9 @@
+package {
+    public namespace AS3 = "http://adobe.com/AS3/2006/builtin";
+
+    public const NaN: Number = 0 / 0;
+
+    public const Infinity: Number = 1 / 0;
+
+    public const undefined = void 0;
+}