[MD settings] fix layout in startup urls and search engines iron-lists

chrome/browser/resources/settings/on_startup_page/startup_urls_page.html

Index: chrome/browser/resources/settings/on_startup_page/startup_urls_page.html
diff --git a/chrome/browser/resources/settings/on_startup_page/startup_urls_page.html b/chrome/browser/resources/settings/on_startup_page/startup_urls_page.html
index 155ded00997fe08d986b55a1f4ec13e3cc07a5f7..420d8dea804dcbb6873390e28a9f8f39d11a1193 100644
--- a/chrome/browser/resources/settings/on_startup_page/startup_urls_page.html
+++ b/chrome/browser/resources/settings/on_startup_page/startup_urls_page.html
@@ -17,31 +17,31 @@
 <dom-module id="settings-startup-urls-page">
   <template>
     <style include="settings-shared action-link iron-flex">
-      #outer {
+      #container {
         @apply(--settings-list-frame-padding);
-        max-height: 395px;  /** Enough height to show six entries. */
-      }
-
-      #container iron-list > settings-startup-url-entry:not(:first-of-type) {
-        border-top: var(--settings-separator-line);
+        /* Show up to six rows before limiting the height and using a scroll
+         * bar. */
+        max-height: calc((var(--settings-row-two-line-min-height) +
+                          var(--settings-separator-height)) * 6);
       }
 
       #container settings-startup-url-entry {
+        border-bottom: var(--settings-separator-line);
         cursor: default;
       }
     </style>
-    <div id="outer" class="layout vertical flex vertical-list">
-      <div id="container" class="scroll-container" scrollable>
-        <iron-list items="[[startupPages_]]" scroll-target="container">
-          <template>
-            <settings-startup-url-entry model="[[item]]"
-                tabindex$="[[tabIndex]]" iron-list-tab-index="[[tabIndex]]"
-                last-focused="{{lastFocused_}}"
-                editable="[[!prefs.session.startup_urls.controlledBy]]">
-            </settings-startup-url-entry>
-          </template>
-        </iron-list>
-      </div>
+    <div id="container" class="scroll-container" scrollable>
+      <iron-list items="[[startupPages_]]" scroll-target="container">
+        <template>
+          <settings-startup-url-entry model="[[item]]"
+              tabindex$="[[tabIndex]]" iron-list-tab-index="[[tabIndex]]"
+              last-focused="{{lastFocused_}}"
+              editable="[[!prefs.session.startup_urls.controlledBy]]">
+          </settings-startup-url-entry>
+        </template>
+      </iron-list>
+    </div>
+    <div class="list-frame vertical-list">
       <template is="dom-if" if="[[!prefs.session.startup_urls.controlledBy]]"
           restamp>
         <div class="list-item" id="addPage">