Add Custom Named property getters for cssStyleDeclaration to determine the existence of a property.

Source/bindings/dart/scripts/templates/interface_h.template

Index: Source/bindings/dart/scripts/templates/interface_h.template
diff --git a/Source/bindings/dart/scripts/templates/interface_h.template b/Source/bindings/dart/scripts/templates/interface_h.template
index 1e2bb5d7ba4f4b5285927da84caba1deef4ef8db..353d0883faa9401b9b3ea4f4c69dcc670122f979 100644
--- a/Source/bindings/dart/scripts/templates/interface_h.template
+++ b/Source/bindings/dart/scripts/templates/interface_h.template
@@ -171,6 +171,11 @@ namespace {{dart_class}}Internal {
     {% endif %}
   {% endfor %}
 
+  {% if dart_class == 'DartCSSStyleDeclaration' %}
+  // TODO(efortuna): Pull in custom functions in a less hacky way!
+  void propertyQuery(Dart_NativeArguments args);
+  {% endif %}
+
 }
 
 }  // namespace WebCore