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

chrome/browser/resources/settings/appearance_page/appearance_page.html

 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-flex-layout/classes/iron-flex-layout.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable.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-icon-button/paper-icon-button-light.html">
 <link rel="import" href="/appearance_page/appearance_browser_proxy.html">
 <link rel="import" href="/controls/controlled_radio_button.html">
 <link rel="import" href="/controls/settings_dropdown_menu.html">
@@ skipping 94 matching lines @@
               pref="{{prefs.webkit.webprefs.default_font_size}}"
               menu-options="[[fontSizeOptions_]]">
           </settings-dropdown-menu>
         </div>
         <div id="customize-fonts-subpage-trigger" class="settings-box two-line"
             on-tap="onCustomizeFontsTap_" actionable>
           <div class="start">
             <div>$i18n{customizeFonts}</div>
             <div class="secondary">$i18n{chooseFonts}</div>
           </div>
-          <button class="icon-arrow-right" is="paper-icon-button-light">
+          <button class="subpage-arrow" is="paper-icon-button-light">
           </button>
         </div>
         <div class="settings-box"
             hidden="[[!pageVisibility.pageZoom]]">
           <div class="start">$i18n{pageZoom}</div>
           <settings-dropdown-menu id="pageZoom" pref="{{defaultZoomLevel_}}"
               menu-options="[[pageZoomOptions_]]">
           </settings-dropdown-menu>
         </div>
       </neon-animatable>
       <template is="dom-if" route-path="/fonts">
         <settings-subpage
             associated-control="[[$$('#customize-fonts-subpage-trigger')]]"
             page-title="$i18n{customizeFonts}">
           <settings-appearance-fonts-page prefs="{{prefs}}">
           </settings-appearance-fonts-page>
         </settings-subpage>
       </template>
     </settings-animated-pages>
   </template>
   <script src="appearance_page.js"></script>
 </dom-module>