Minor fixes to the Chrome Cleanup WebUI

chrome/browser/resources/settings/chrome_cleanup_page/chrome_cleanup_page.html

 <link rel="import" href="chrome://resources/html/util.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-spinner/paper-spinner.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/color.html">
 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="../controls/controlled_button.html">
 <link rel="import" href="../controls/settings_toggle_button.html">
@@ skipping 41 matching lines @@
             hidden="[[!isRemoving_]]">
         </paper-spinner>
         <iron-icon icon="[[statusIcon_]]" hidden="[[isRemoving_]]"
             class$="[[statusIconClassName_]]"
             id="status-icon">
         </iron-icon>
       </div>
       <div class="start">[[title_]]</div>
       <template is="dom-if" if="[[showActionButton_]]">
         <div class="separator"></div>
-        <paper-button id="action-button" on-tap="proceed_">
+        <paper-button id="action-button" class="primary-button"
+            on-tap="proceed_">
           [[actionButtonLabel_]]
         </paper-button>
       </template>
     </div>
     <div id="details-container"
          class="settings-box two-line" hidden="[[!showDetails_]]">
       <div>[[detailsDescription]]</div>
     </div>
     <div class="settings-box continuation" hidden="[[!showDetails_]]">
       <div class="show-files-container start" hidden="[[showFilesToRemove_]]">
         <paper-button id="show-files-button" on-tap="showFiles_">
           $i18n{chromeCleanupLinkShowFiles}
         </paper-button>
       </div>
       <div hidden="[[!showFilesToRemove_]]">
         <ul id="files-to-remove-list" class="secondary">
           <template is="dom-repeat" items="[[filesToRemove_]]" as="fileName">
             <li>[[fileName]]</li>
           </template>
         </ul>
       </div>
     </div>
   </template>
   <script src="chrome_cleanup_page.js"></script>
 </dom-module>