MD History: Fix item sizing in small windows

chrome/browser/resources/md_history/grouped_list.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-collapse/iron-collapse.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://history/constants.html">
 <link rel="import" href="chrome://history/history_item.html">
 <link rel="import" href="chrome://history/shared_style.html">
 
 <dom-module id="history-grouped-list">
   <template>
     <style include="shared-style">
       :host {
         display: block;
         overflow: auto;
         position: relative;
       }
 
       #main-container {
+        @apply(--card-sizing);
         align-items: center;
         display: flex;
         flex-direction: column;
-        padding: var(--first-card-padding-top) var(--card-padding-side);
+        padding-top: var(--first-card-padding-top);
       }
 
       .domain-heading {
         align-items: center;
         display: flex;
         height: var(--item-height);
         padding: 0 20px;
       }
 
       .domain-count {
@@ skipping 22 matching lines @@
 
       .domain-heading-text {
         flex: 1 1 0;
       }
 
       .dropdown-indicator {
         max-width: 16px;
       }
 
       history-item {
-        --border-style: none;
         padding-left: 20px;
       }
     </style>
     <div id="no-results" class="centered-message"
         hidden$="[[hasResults_(groupedHistoryData_.length)]]">
       [[noResultsMessage_(searchedTerm, querying)]]
     </div>
     <div id="main-container"
         hidden$="[[!hasResults_(groupedHistoryData_.length)]]">
       <template is="dom-repeat" items="[[groupedHistoryData_]]" as="group"
@@ skipping 19 matching lines @@
               <iron-collapse opened="{{domain.expanded}}" id="collapse">
                 <template is="dom-if" if="[[domain.rendered]]">
                   <template is="dom-repeat" items="[[domain.visits]]"
                       as="item" initial-count="5" index-as="itemIndex">
                     <history-item item="[[item]]"
                         starred="[[item.starred]]"
                         selected="{{item.selected}}"
                         has-time-gap="[[needsTimeGap_(
                             groupIndex, domainIndex, itemIndex)]]"
                         search-term="[[searchedTerm]]"
-                        number-of-items="[[historyData.length]]">
+                        number-of-items="[[historyData.length]]"
+                        embedded>
                     </history-item>
                   </template>
                 </template>
               </iron-collapse>
             </div>
           </template>
         </div>
       </template>
     </div>
     </template>
   <script src="chrome://history/grouped_list.js"></script>
 </dom-module>