Fix import for gr-diff-preferences

This was broken by Ifd950bd42.

Change-Id: Ifa5d44201cd6b99b9df2c089af9d234d715b6eca
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.html b/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.html
index 5cff316..ae53f76 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.html
@@ -18,7 +18,7 @@
 <link rel="import" href="../../../bower_components/polymer/polymer.html">
 <link rel="import" href="../../../styles/shared-styles.html">
 <link rel="import" href="../../shared/gr-button/gr-button.html">
-<link rel="import" href="../../shared/gr-diff-preferences/gr-preferences.html">
+<link rel="import" href="../../shared/gr-diff-preferences/gr-diff-preferences.html">
 <link rel="import" href="../../shared/gr-overlay/gr-overlay.html">
 
 <dom-module id="gr-diff-preferences-dialog">