[MD History] Move Clear Browsing Data button to sidebar.

chrome/browser/resources/md_history/side_bar.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-flex-layout/iron-flex-layout.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-item/paper-item.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-listbox/paper-listbox.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-ripple/paper-ripple.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/color.html">
 <link rel="import" href="chrome://history/shared_style.html">
 
 <dom-module id="history-side-bar">
   <template>
     <style include="shared-style">
       :host {
         padding-top: 5px;
         width: var(--side-bar-width);
       }
 
+      div.separator {
+        background-color: rgba(0, 0, 0, 0.08);
+        height: 1px;
+        margin: 8px 0;
+      }
+
+      #clear-browsing-data {
+        text-transform: uppercase;
+      }
+
       paper-item {
         -webkit-padding-start: 25px;
         cursor: pointer;
         font-size: 14px;
         font-weight: 500;
       }
 
       paper-item.iron-selected {
         color: var(--google-blue-500);
         font-weight: 500;
       }
 
       paper-listbox {
         -webkit-user-select: none;
         background-color: transparent;
         color: #5a5a5a;
       }
     </style>
-    <paper-listbox id="overflow-menu" selected="0" on-iron-select="onSelect_">
+    <paper-listbox id="overflow-menu" selected="0" on-iron-select="onSelect_" selectable="paper-item">
       <paper-item view-id="history-list">
         <div>$i18n{historyMenuItem}</div>
         <paper-ripple></paper-ripple>
       </paper-item>
       <paper-item view-id="history-synced-device-manager">
         <div>$i18n{openTabsMenuItem}</div>
         <paper-ripple></paper-ripple>
       </paper-item>
+      <div class="separator"></div>
+      <paper-item on-tap="onClearBrowsingDataTap_" id="clear-browsing-data">

[tsergeant, 2016/05/05 21:29:31]

It's a little weird to use a paper-item here since it will end up selecting a
null page while it's navigating to clear browsing data. The history page goes
blank for a second before navigating to settings. Not a big deal, but it would
be nice to fix it.

[calamity, 2016/05/10 03:15:26]

Fixed that issue. I think paper-item is nice because it reflects the style of
the other items. I tried button. It looked very out of place and inconsistent.

+        <div>$i18n{clearBrowsingData}</div>
+        <paper-ripple></paper-ripple>
+      </paper-item>
     </paper-listbox>
   </template>
   <script src="chrome://history/side_bar.js"></script>
 </dom-module>