diff --git a/components/script/layout_wrapper.rs b/components/script/layout_wrapper.rs
index 7c7c9cc3505..a916ee73512 100644
--- a/components/script/layout_wrapper.rs
+++ b/components/script/layout_wrapper.rs
@@ -391,6 +391,11 @@ impl<'le> TElement for ServoLayoutElement<'le> {
         self.get_attr(namespace, attr).is_some()
     }
 
+    #[inline]
+    fn attr_equals(&self, namespace: &Namespace, attr: &Atom, val: &Atom) -> bool {
+        self.get_attr(namespace, attr).map_or(false, |x| x == val)
+    }
+
     #[inline]
     fn get_attr(&self, namespace: &Namespace, name: &Atom) -> Option<&str> {
         unsafe {
diff --git a/components/style/dom.rs b/components/style/dom.rs
index 436bf57aebd..9cdce7b3852 100644
--- a/components/style/dom.rs
+++ b/components/style/dom.rs
@@ -208,6 +208,7 @@ pub trait TElement : Sized + Copy + Clone + ElementExt + PresentationalHintsSynt
     fn get_state(&self) -> ElementState;
 
     fn has_attr(&self, namespace: &Namespace, attr: &Atom) -> bool;
+    fn attr_equals(&self, namespace: &Namespace, attr: &Atom, value: &Atom) -> bool;
 
     fn get_attr<'a>(&'a self, namespace: &Namespace, attr: &Atom) -> Option<&'a str>;
 
diff --git a/components/style/matching.rs b/components/style/matching.rs
index aa7d751267d..f97ee2aab2c 100644
--- a/components/style/matching.rs
+++ b/components/style/matching.rs
@@ -39,11 +39,9 @@ fn create_common_style_affecting_attributes_from_element<E: TElement>(element: &
                 }
             }
             CommonStyleAffectingAttributeMode::IsEqual(target_value, flag) => {
-                match element.get_attr(&ns!(), &attribute_info.atom) {
-                    Some(element_value) if element_value == target_value => {
-                        flags.insert(flag)
-                    }
-                    _ => {}
+                let atom = Atom::from(target_value); // FIXME(bholley): This goes away in the next patch.
+                if element.attr_equals(&ns!(), &attribute_info.atom, &atom) {
+                    flags.insert(flag)
                 }
             }
         }
@@ -301,19 +299,14 @@ impl<C: ComputedValues> StyleSharingCandidate<C> {
                     }
                 }
                 CommonStyleAffectingAttributeMode::IsEqual(target_value, flag) => {
-                    match element.get_attr(&ns!(), &attribute_info.atom) {
-                        Some(ref element_value) if self.common_style_affecting_attributes
-                                                       .contains(flag) &&
-                                                       *element_value != target_value => {
+                    let atom = Atom::from(target_value); // FIXME(bholley): This goes away in the next patch.
+                    let contains = self.common_style_affecting_attributes.contains(flag);
+                    if element.has_attr(&ns!(), &attribute_info.atom) {
+                        if !contains || !element.attr_equals(&ns!(), &attribute_info.atom, &atom) {
                             return false
                         }
-                        Some(_) if !self.common_style_affecting_attributes.contains(flag) => {
-                            return false
-                        }
-                        None if self.common_style_affecting_attributes.contains(flag) => {
-                            return false
-                        }
-                        _ => {}
+                    } else if contains {
+                        return false
                     }
                 }
             }
diff --git a/ports/geckolib/wrapper.rs b/ports/geckolib/wrapper.rs
index 7dc4545be2f..247d3b9216c 100644
--- a/ports/geckolib/wrapper.rs
+++ b/ports/geckolib/wrapper.rs
@@ -369,6 +369,17 @@ impl<'le> TElement for GeckoElement<'le> {
         }
     }
 
+    #[inline]
+    fn attr_equals(&self, namespace: &Namespace, attr: &Atom, val: &Atom) -> bool {
+        unsafe {
+            bindings::Gecko_AttrEquals(self.element,
+                                       namespace.0.as_ptr(),
+                                       attr.as_ptr(),
+                                       val.as_ptr(),
+                                       /* ignoreCase = */ false)
+        }
+    }
+
     #[inline]
     fn get_attr<'a>(&'a self, namespace: &Namespace, name: &Atom) -> Option<&'a str> {
         unsafe {