[MD settings] use arrow-forward to switch direction in rtl

chrome/browser/resources/settings/site_settings/site_list.html

 <link rel="import" href="chrome://resources/cr_elements/icons.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-dropdown/iron-dropdown.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-icon-button/paper-icon-button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-menu/paper-submenu.html">
 <link rel="import" href="/i18n_setup.html">
 <link rel="import" href="/icons.html">
 <link rel="import" href="/route.html">
@@ skipping 65 matching lines @@
                       hidden$="[[!showSessionOnlyActionForSite_(item)]]">
                     $i18n{siteSettingsActionSessionOnly}
                   </button>
                   <button class="dropdown-item" role="option" id="reset"
                       on-tap="onResetTap_">
                     $i18n{siteSettingsActionReset}
                   </button>
                 </div>
               </iron-dropdown>
             </template>
+            <template is="dom-if" if="[[enableSiteSettings_]]">
+              <div on-tap="onOriginTap_" actionable>
+                <button class="subpage-arrow" is="paper-icon-button-light">
+                </button>
+              </div>
+            </template>

[dschuyler, 2016/10/17 21:16:35]

Now that the site details are behind a flag, these arrows
need to be updated to use the same flag.

           </div>
         </template>
 
         <template is="dom-if" if="[[!allSites]]">
           <div class="list-item list-button" on-tap="onAddSiteTap_">
             $i18n{addSiteLink}
           </div>
         </template>
       </div>
     </paper-submenu>
   </template>
   <script src="site_list.js"></script>
 </dom-module>