Settings: fix assertion failure when searching

If anything on the new /security page is searched for, search
fails an assert()ion because there is no associated control.

So we just add no-search to the security page for now.

R=rbpotter@chromium.org

Fixed: 1038420
Change-Id: I91bf27c93e31eb4898e9dd74701c3dddadd5b2be
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1984636
Auto-Submit: Dan Beam <dbeam@chromium.org>
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: Dan Beam <dbeam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#728024}

chrome/browser/resources/settings/privacy_page/privacy_page.html

@@ -168,10 +168,8 @@
         </settings-subpage>
       </template>
 
-      <template is="dom-if" route-path="/security">
-        <settings-subpage
-            id="security"
-            page-title="$i18n{securityPageTitle}">
+      <template is="dom-if" route-path="/security" no-search>
+        <settings-subpage id="security" page-title="$i18n{securityPageTitle}">
           <settings-security-page prefs="{{prefs}}"
               sync-status="[[syncStatus]]">
           </settings-security-page>