diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index c8eda80834f9..b25d596baa26 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -3966,7 +3966,23 @@ def __init__(self, descriptor):
         CGProxySpecialOperation.__init__(self, descriptor, 'IndexedSetter')
 
 
-class CGProxyNamedGetter(CGProxySpecialOperation):
+class CGProxyNamedOperation(CGProxySpecialOperation):
+    """
+    Class to generate a call to a named operation.
+    """
+    def __init__(self, descriptor, name):
+        CGProxySpecialOperation.__init__(self, descriptor, name)
+
+    def define(self):
+        # Our first argument is the id we're getting.
+        argName = self.arguments[0].identifier.name
+        return ("let %s = jsid_to_str(cx, id);\n"
+                "let this = UnwrapProxy(proxy);\n"
+                "let this = &*this;\n" % argName +
+                CGProxySpecialOperation.define(self))
+
+
+class CGProxyNamedGetter(CGProxyNamedOperation):
     """
     Class to generate a call to an named getter. If templateValues is not None
     the returned value will be wrapped with wrapForType using templateValues.
@@ -3976,7 +3992,16 @@ def __init__(self, descriptor, templateValues=None):
         CGProxySpecialOperation.__init__(self, descriptor, 'NamedGetter')
 
 
-class CGProxyNamedSetter(CGProxySpecialOperation):
+class CGProxyNamedPresenceChecker(CGProxyNamedGetter):
+    """
+    Class to generate a call that checks whether a named property exists.
+    For now, we just delegate to CGProxyNamedGetter
+    """
+    def __init__(self, descriptor):
+        CGProxyNamedGetter.__init__(self, descriptor)
+
+
+class CGProxyNamedSetter(CGProxyNamedOperation):
     """
     Class to generate a call to a named setter.
     """
@@ -3984,7 +4009,7 @@ def __init__(self, descriptor):
         CGProxySpecialOperation.__init__(self, descriptor, 'NamedSetter')
 
 
-class CGProxyNamedDeleter(CGProxySpecialOperation):
+class CGProxyNamedDeleter(CGProxyNamedOperation):
     """
     Class to generate a call to a named deleter.
     """
@@ -4057,9 +4082,6 @@ def getBody(self):
             # properties that shadow prototype properties.
             namedGet = ("\n" +
                         "if RUST_JSID_IS_STRING(id) != 0 && !has_property_on_prototype(cx, proxy, id) {\n" +
-                        "    let name = jsid_to_str(cx, id);\n" +
-                        "    let this = UnwrapProxy(proxy);\n" +
-                        "    let this = &*this;\n" +
                         CGIndenter(CGProxyNamedGetter(self.descriptor, templateValues)).define() + "\n" +
                         "}\n")
         else:
@@ -4121,9 +4143,6 @@ def getBody(self):
             if not self.descriptor.operations['NamedCreator'] is namedSetter:
                 raise TypeError("Can't handle creator that's different from the setter")
             set += ("if RUST_JSID_IS_STRING(id) != 0 {\n" +
-                    "    let name = jsid_to_str(cx, id);\n" +
-                    "    let this = UnwrapProxy(proxy);\n" +
-                    "    let this = &*this;\n" +
                     CGIndenter(CGProxyNamedSetter(self.descriptor)).define() +
                     "    (*opresult).code_ = 0; /* SpecialCodes::OkCode */\n" +
                     "    return JSTrue;\n" +
@@ -4132,9 +4151,6 @@ def getBody(self):
                     "}\n")
         else:
             set += ("if RUST_JSID_IS_STRING(id) != 0 {\n" +
-                    "    let name = jsid_to_str(cx, id);\n" +
-                    "    let this = UnwrapProxy(proxy);\n" +
-                    "    let this = &*this;\n" +
                     CGIndenter(CGProxyNamedGetter(self.descriptor)).define() +
                     "    if (found) {\n"
                     # TODO(Issue 5876)
@@ -4165,10 +4181,7 @@ def __init__(self, descriptor):
     def getBody(self):
         set = ""
         if self.descriptor.operations['NamedDeleter']:
-            set += ("let name = jsid_to_str(cx, id);\n" +
-                    "let this = UnwrapProxy(proxy);\n" +
-                    "let this = &*this;\n" +
-                    "%s") % (CGProxyNamedDeleter(self.descriptor).define())
+            set += CGProxyNamedDeleter(self.descriptor).define()
         set += "return proxyhandler::delete(%s) as u8;" % ", ".join(a.name for a in self.args)
         return set
 
@@ -4253,9 +4266,6 @@ def getBody(self):
         namedGetter = self.descriptor.operations['NamedGetter']
         if namedGetter:
             named = ("if RUST_JSID_IS_STRING(id) != 0 && !has_property_on_prototype(cx, proxy, id) {\n" +
-                     "    let name = jsid_to_str(cx, id);\n" +
-                     "    let this = UnwrapProxy(proxy);\n" +
-                     "    let this = &*this;\n" +
                      CGIndenter(CGProxyNamedGetter(self.descriptor)).define() + "\n" +
                      "    *bp = found as u8;\n"
                      "    return JSTrue;\n"
@@ -4329,9 +4339,6 @@ def getBody(self):
         namedGetter = self.descriptor.operations['NamedGetter']
         if namedGetter:
             getNamed = ("if (RUST_JSID_IS_STRING(id) != 0) {\n" +
-                        "    let name = jsid_to_str(cx, id);\n" +
-                        "    let this = UnwrapProxy(proxy);\n" +
-                        "    let this = &*this;\n" +
                         CGIndenter(CGProxyNamedGetter(self.descriptor, templateValues)).define() +
                         "}\n")
         else:
diff --git a/components/script/dom/webidls/TestBindingProxy.webidl b/components/script/dom/webidls/TestBindingProxy.webidl
index 64a15b356587..8293b7c06aee 100644
--- a/components/script/dom/webidls/TestBindingProxy.webidl
+++ b/components/script/dom/webidls/TestBindingProxy.webidl
@@ -15,9 +15,9 @@
 interface TestBindingProxy : TestBinding {
   readonly attribute unsigned long length;
 
-  getter DOMString getNamedItem(DOMString name);
+  getter DOMString getNamedItem(DOMString item_name);
 
-  setter creator void setNamedItem(DOMString name, DOMString value);
+  setter creator void setNamedItem(DOMString item_name, DOMString value);
 
   getter DOMString getItem(unsigned long index);