use local reference for wrap.

src/lib/dom-api.html

@@ -60,7 +60,7 @@
 
         var n = node;
         // wrap document for SD polyfill
-        var wrappedDocument = Polymer.DomApi.wrap(document);
+        var wrappedDocument = wrap(document);
 
         // walk from node to `this` or `document`
         while (n && n !== wrappedDocument && n !== this.node) {

src/standard/gestures.html

@@ -12,6 +12,8 @@
 
   'use strict';
 
+  var wrap = Polymer.DomApi.wrap;
+
   // detect native touch action support
   var HAS_NATIVE_TA = typeof document.head.style.touchAction === 'string';
   var GESTURE_KEY = '__polymerGestures';
@@ -199,7 +201,7 @@
     handleNative: function(ev) {
       var handled;
       var type = ev.type;
-      var node = Polymer.DomApi.wrap(ev.currentTarget);
+      var node = wrap(ev.currentTarget);
       var gobj = node[GESTURE_KEY];
       if (!gobj) {
         return;
@@ -296,7 +298,7 @@
     // automate the event listeners for the native events
     add: function(node, evType, handler) {
       // SD polyfill: handle case where `node` is unwrapped, like `document`
-      node = Polymer.DomApi.wrap(node);
+      node = wrap(node);
       var recognizer = this.gestures[evType];
       var deps = recognizer.deps;
       var name = recognizer.name;
@@ -329,7 +331,7 @@
     // automate event listener removal for native events
     remove: function(node, evType, handler) {
       // SD polyfill: handle case where `node` is unwrapped, like `document`
-      node = Polymer.DomApi.wrap(node);
+      node = wrap(node);
       var recognizer = this.gestures[evType];
       var deps = recognizer.deps;
       var name = recognizer.name;