Implement client{Top, Left, Height, Width} element properties

components/script/dom/element.rs

@@ -1296,6 +1296,26 @@ impl<'a> ElementMethods for &'a Element {
             rect.origin.x + rect.size.width)
     }
 
+    fn ClientTop(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().origin.y
+    }
+
+    fn ClientLeft(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().origin.x
+    }
+
+    fn ClientWidth(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().size.width
+    }
+
+    fn ClientHeight(self) -> i32 {
+        let node = NodeCast::from_ref(self);
+        node.get_client_rect().size.height
+    }
+
     // https://dvcs.w3.org/hg/innerhtml/raw-file/tip/index.html#widl-Element-innerHTML
     fn GetInnerHTML(self) -> Fallible<DOMString> {
         //XXX TODO: XML case