cros: Updated autoclick section for md-settings.

chrome/browser/resources/settings/a11y_page/manage_a11y_page.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button-light.html">
 <link rel="import" href="/controls/settings_checkbox.html">
 <link rel="import" href="/i18n_setup.html">
 <link rel="import" href="/route.html">
 <link rel="import" href="/settings_shared_css.html">
 <link rel="import" href="/settings_vars_css.html">
 
 <dom-module id="settings-manage-a11y-page">
   <template>
@@ skipping 99 matching lines @@
 
       <h2>$i18n{mouseAndTouchpadHeading}</h2>
       <div class="settings-box block first indented">
         <settings-checkbox label="$i18n{clickOnStopLabel}"
             pref="{{prefs.settings.a11y.autoclick}}">
         </settings-checkbox>
         <div class="list-item settings-checkbox-spacer">
           <div>$i18n{delayBeforeClickLabel}</div>
           <settings-dropdown-menu
               pref="{{prefs.settings.a11y.autoclick_delay_ms}}"
-              menu-options="[[autoClickDelayOptions_]]">
+              menu-options="[[autoClickDelayOptions_]]"
+              disabled="[[!prefs.settings.a11y.autoclick.value]]">
           </settings-dropdown-menu>
         </div>
         <settings-checkbox label="$i18n{tapDraggingLabel}"
             pref="{{prefs.settings.touchpad.enable_tap_dragging}}">
         </settings-checkbox>
         <settings-checkbox label="$i18n{largeMouseCursorLabel}"
             pref="{{prefs.settings.a11y.large_cursor_enabled}}">
         </settings-checkbox>
         <settings-checkbox pref="{{prefs.settings.a11y.cursor_highlight}}"
             label="$i18n{cursorHighlightLabel}">
@@ skipping 20 matching lines @@
     <div class="settings-box two-line" on-tap="onMoreFeaturesTap_" actionable>
       <div class="start">
         <div>$i18n{additionalFeaturesTitle}</div>
         <div class="secondary">$i18n{a11yWebStore}</div>
       </div>
       <button class="icon-external" is="paper-icon-button-light"></button>
     </div>
   </template>
   <script src="manage_a11y_page.js"></script>
 </dom-module>