diff --git a/components/style/binding_tools/regen.py b/components/style/binding_tools/regen.py
index 53ade1bf1e7..d924d31d292 100755
--- a/components/style/binding_tools/regen.py
+++ b/components/style/binding_tools/regen.py
@@ -236,10 +236,12 @@ COMPILATION_TARGETS = {
         "target_dir": "../gecko_bindings",
         "blacklist_types": [
             "nsACString_internal",
+            "nsAString_internal",
         ],
         "raw_lines": [
-            "pub use nsstring::nsACString;",
+            "pub use nsstring::{nsACString, nsAString};",
             "type nsACString_internal = nsACString;",
+            "type nsAString_internal = nsAString;"
         ],
         "flags": [
             "--ignore-methods",
diff --git a/components/style/gecko_bindings/bindings.rs b/components/style/gecko_bindings/bindings.rs
index e9cb580d217..f2a2c19f1a5 100644
--- a/components/style/gecko_bindings/bindings.rs
+++ b/components/style/gecko_bindings/bindings.rs
@@ -1,7 +1,8 @@
 /* automatically generated by rust-bindgen */
 
-pub use nsstring::nsACString;
+pub use nsstring::{nsACString, nsAString};
 type nsACString_internal = nsACString;
+type nsAString_internal = nsAString;
 pub type ServoComputedValuesStrong = ::gecko_bindings::sugar::ownership::Strong<ServoComputedValues>;
 pub type ServoComputedValuesBorrowedOrNull<'a> = Option<&'a ServoComputedValues>;
 pub type ServoComputedValuesBorrowed<'a> = &'a ServoComputedValues;
@@ -936,6 +937,19 @@ extern "C" {
                                                         RawServoDeclarationBlockBorrowed,
                                                     buffer: *mut nsString);
 }
+extern "C" {
+    pub fn Servo_DeclarationBlock_Count(declarations:
+                                            RawServoDeclarationBlockBorrowed)
+     -> u32;
+}
+extern "C" {
+    pub fn Servo_DeclarationBlock_GetNthProperty(declarations:
+                                                     RawServoDeclarationBlockBorrowed,
+                                                 index: u32,
+                                                 result:
+                                                     *mut nsAString_internal)
+     -> bool;
+}
 extern "C" {
     pub fn Servo_CSSSupports(name: *const nsACString_internal,
                              value: *const nsACString_internal) -> bool;
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index ba4a023b715..b266a4c7084 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -7,6 +7,7 @@ use cssparser::{Parser, ToCss};
 use env_logger;
 use euclid::Size2D;
 use parking_lot::RwLock;
+use std::fmt::Write;
 use std::mem::transmute;
 use std::sync::{Arc, Mutex};
 use style::arc_ptr_eq;
@@ -474,6 +475,25 @@ pub extern "C" fn Servo_DeclarationBlock_SerializeOneValue(
     }
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_Count(declarations: RawServoDeclarationBlockBorrowed) -> u32 {
+     let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+     declarations.read().declarations.len() as u32
+}
+
+#[no_mangle]
+pub extern "C" fn Servo_DeclarationBlock_GetNthProperty(declarations: RawServoDeclarationBlockBorrowed,
+                                                        index: u32, result: *mut nsAString) -> bool {
+    let declarations = RwLock::<PropertyDeclarationBlock>::as_arc(&declarations);
+    if let Some(&(ref decl, _)) = declarations.read().declarations.get(index as usize) {
+        let result = unsafe { result.as_mut().unwrap() };
+        write!(result, "{}", decl.name()).unwrap();
+        true
+    } else {
+        false
+    }
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_CSSSupports(property: *const nsACString, value: *const nsACString) -> bool {
     let property = unsafe { property.as_ref().unwrap().as_str_unchecked() };