MD History: Fix position of Clear Browsing Data menu promo

ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-media-query/iron-media-query.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html">
 
 <dom-module id="cr-toolbar">
   <template>
     <style>
       :host {
         --cr-toolbar-field-width: 580px;
@@ skipping 11 matching lines @@
         font-size: 123%;
         font-weight: 400;
         text-overflow: ellipsis;
         overflow: hidden;
         white-space: nowrap;
       }
 
       #leftContent {
         /* margin-start here must match margin-end on #rightContent. */
         -webkit-margin-start: 12px;
+        position: relative;
         transition: opacity 100ms;
       }
 
       #leftSpacer {
         -webkit-margin-start: 6px;
         align-items: center;
         display: flex;
       }
 
       #menuButton {
@@ skipping 110 matching lines @@
       <iron-media-query query="(max-width: 900px)" query-matches="{{narrow_}}">
       </iron-media-query>
     </div>
 
     <div id="rightContent">
       <content select=".more-actions"></content>
     </div>
   </template>
   <script src="cr_toolbar.js"></script>
 </dom-module>