Roll Polymer from 1.5.0 -> 1.6.0 to pick up native CSS custom props

third_party/polymer/v1_0/components-chromium/iron-location/iron-location-extracted.js

 'use strict';
 
   Polymer({
     is: 'iron-location',
     properties: {
       /**
        * The pathname component of the URL.
        */
       path: {
         type: String,
@@ skipping 161 matching lines @@
       // If another event handler has stopped this event then there's nothing
       // for us to do. This can happen e.g. when there are multiple
       // iron-location elements in a page.
       if (event.defaultPrevented) {
         return;
       }
       var href = this._getSameOriginLinkHref(event);
       if (!href) {
         return;
       }
+      event.preventDefault();
+      // If the navigation is to the current page we shouldn't add a history
+      // entry or fire a change event.
+      if (href === window.location.href) {
+        return;
+      }
       window.history.pushState({}, '', href);
       this.fire('location-changed', {}, {node: window});
-      event.preventDefault();
     },
     /**
      * Returns the absolute URL of the link (if any) that this click event
      * is clicking on, if we can and should override the resulting full
      * page navigation. Returns null otherwise.
      *
      * @param {MouseEvent} event .
      * @return {string?} .
      */
     _getSameOriginLinkHref: function(event) {
@@ skipping 62 matching lines @@
       var normalizedHref = url.pathname + url.search + url.hash;
 
       // If we've been configured not to handle this url... don't handle it!
       if (this._urlSpaceRegExp &&
           !this._urlSpaceRegExp.test(normalizedHref)) {
         return null;
       }
       // Need to use a full URL in case the containing page has a base URI.
       var fullNormalizedHref = new URL(
           normalizedHref, window.location.href).href;
-      // If the navigation is to the current page we shouldn't add a history
-      // entry.
-      if (fullNormalizedHref === window.location.href) {
-        return null;
-      }
       return fullNormalizedHref;
     },
     _makeRegExp: function(urlSpaceRegex) {
       return RegExp(urlSpaceRegex);
     }
   });