diff --git a/lib/mixins/element-mixin.html b/lib/mixins/element-mixin.html
index 2fed46d2b8..3f0483888f 100644
--- a/lib/mixins/element-mixin.html
+++ b/lib/mixins/element-mixin.html
@@ -21,8 +21,6 @@
 (function() {
   'use strict';
 
-  const ABS_URL = /(^\/)|(^#)|(^[\w-\d]*:)/;
-
   /**
    * Element class mixin that provides the core API for Polymer's meta-programming
    * features including template stamping, data-binding, attribute deserialization,
@@ -635,11 +633,6 @@
        * @return {string} Rewritten URL relative to base
        */
       resolveUrl(url, base) {
-        // Preserve backward compatibility with `this.resolveUrl('/foo')` resolving
-        // against the main document per #2448
-        if (url && ABS_URL.test(url)) {
-          return url;
-        }
         if (!base && this.importPath) {
           base = Polymer.ResolveUrl.resolveUrl(this.importPath);
         }
diff --git a/lib/utils/resolve-url.html b/lib/utils/resolve-url.html
index 612847b1ce..357ef6a322 100644
--- a/lib/utils/resolve-url.html
+++ b/lib/utils/resolve-url.html
@@ -15,6 +15,7 @@
     'use strict';
 
     let CSS_URL_RX = /(url\()([^)]*)(\))/g;
+    let ABS_URL = /(^\/)|(^#)|(^[\w-\d]*:)/;
     let workingURL;
     let resolveDoc;
     /**
@@ -26,6 +27,9 @@
      * @return {string} resolved URL
      */
     function resolveUrl(url, baseURI) {
+      if (url && ABS_URL.test(url)) {
+        return url;
+      }
       // Lazy feature detection.
       if (workingURL === undefined) {
         workingURL = false;
diff --git a/test/unit/resolveurl.html b/test/unit/resolveurl.html
index ccf16ea873..8b08f692d3 100644
--- a/test/unit/resolveurl.html
+++ b/test/unit/resolveurl.html
@@ -157,12 +157,6 @@
         assert.equal(actual, expected);
       });
     });
-
-    suite('Polymer.ResolveUrl', function() {
-      test('appends absolute url to basePath', function() {
-        assert.equal(Polymer.ResolveUrl.resolveUrl('/foo', 'http://localhost'), 'http://localhost/foo');
-      });
-    });
   </script>
 </body>
 </html>