diff --git a/components/script/dom/cssstyledeclaration.rs b/components/script/dom/cssstyledeclaration.rs
index cacb5afb1a7d..7d4feeb40ab7 100644
--- a/components/script/dom/cssstyledeclaration.rs
+++ b/components/script/dom/cssstyledeclaration.rs
@@ -9,7 +9,7 @@ use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, JSRef, OptionalRootedRootable, Temporary};
 use dom::bindings::utils::{Reflectable, Reflector, reflect_dom_object};
 use dom::document::DocumentHelpers;
-use dom::element::{Element, ElementHelpers};
+use dom::element::{Element, ElementHelpers, StylePriority};
 use dom::htmlelement::HTMLElement;
 use dom::node::{window_from_node, document_from_node, NodeDamage, Node};
 use dom::window::Window;
@@ -222,7 +222,8 @@ impl<'a> CSSStyleDeclarationMethods for JSRef<'a, CSSStyleDeclaration> {
         // Step 8
         for decl in decl_block.normal.iter() {
             // Step 9
-            element.update_inline_style(decl.clone(), !priority.is_empty());
+            let style_priority = if priority.is_empty() { StylePriority::Normal } else { StylePriority::Important };
+            element.update_inline_style(decl.clone(), style_priority);
         }
 
         let document = document_from_node(element).root();
@@ -259,7 +260,8 @@ impl<'a> CSSStyleDeclarationMethods for JSRef<'a, CSSStyleDeclaration> {
         // Step 5
         for decl in decl_block.normal.iter() {
             // Step 6
-            element.update_inline_style(decl.clone(), !priority.is_empty());
+            let style_priority = if priority.is_empty() { StylePriority::Normal } else { StylePriority::Important };
+            element.update_inline_style(decl.clone(), style_priority);
         }
 
         let document = document_from_node(element).root();
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index b1d85ef8c741..ca2d6109f12d 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -456,6 +456,12 @@ impl LayoutElementHelpers for JS<Element> {
     }
 }
 
+#[deriving(PartialEq)]
+pub enum StylePriority {
+    Important,
+    Normal,
+}
+
 pub trait ElementHelpers<'a> {
     fn html_element_in_html_document(self) -> bool;
     fn local_name(self) -> &'a Atom;
@@ -467,7 +473,7 @@ pub trait ElementHelpers<'a> {
     fn summarize(self) -> Vec<AttrInfo>;
     fn is_void(self) -> bool;
     fn remove_inline_style_property(self, property: DOMString);
-    fn update_inline_style(self, property_decl: style::PropertyDeclaration, important: bool);
+    fn update_inline_style(self, property_decl: style::PropertyDeclaration, style_priority: StylePriority);
     fn get_inline_style_declaration(self, property: &Atom) -> Option<style::PropertyDeclaration>;
     fn get_important_inline_style_declaration(self, property: &Atom) -> Option<style::PropertyDeclaration>;
 }
@@ -555,10 +561,10 @@ impl<'a> ElementHelpers<'a> for JSRef<'a, Element> {
         });
     }
 
-    fn update_inline_style(self, property_decl: style::PropertyDeclaration, important: bool) {
+    fn update_inline_style(self, property_decl: style::PropertyDeclaration, style_priority: StylePriority) {
         let mut inline_declarations = self.style_attribute().borrow_mut();
         if let Some(ref mut declarations) = *inline_declarations.deref_mut() {
-            let existing_declarations = if important {
+            let existing_declarations = if style_priority == StylePriority::Important {
                 declarations.important.make_unique()
             } else {
                 declarations.normal.make_unique()
@@ -574,7 +580,7 @@ impl<'a> ElementHelpers<'a> for JSRef<'a, Element> {
             return;
         }
 
-        let (important, normal) = if important {
+        let (important, normal) = if style_priority == StylePriority::Important {
             (vec!(property_decl), vec!())
         } else {
             (vec!(), vec!(property_decl))