Make lists in the passwords section aware of the scroll target.

chrome/browser/resources/settings/settings_ui/settings_ui.js

Index: chrome/browser/resources/settings/settings_ui/settings_ui.js
diff --git a/chrome/browser/resources/settings/settings_ui/settings_ui.js b/chrome/browser/resources/settings/settings_ui/settings_ui.js
index 59d21d3c3255ef5b292e9085314a9aa3d34ac05c..6d7a3d23d5544d57327a63f94499a0355c71d81b 100644
--- a/chrome/browser/resources/settings/settings_ui/settings_ui.js
+++ b/chrome/browser/resources/settings/settings_ui/settings_ui.js
@@ -43,6 +43,18 @@ Polymer({
      * @private {!GuestModePageVisibility}
      */
     pageVisibility_: Object,
+
+    /**
+     * The scroll target for the lists in this section.
+     * @type {Element}
+     * @private
+     */
+    scrollTarget_: {
+      type: HTMLElement,
+      value: function() {
+        return this.$.headerPanel.scroller;
+      }
+    }
   },
 
   /** @override */