[MD Bookmarks] Add edit folder.

chrome/browser/resources/md_bookmarks/list.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_action_menu/cr_action_menu.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_dialog/cr_dialog.html">
 <link rel="import" href="chrome://resources/cr_elements/shared_style_css.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="chrome://resources/polymer/v1_0/paper-input/paper-input.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/shadow.html">
 <link rel="import" href="chrome://bookmarks/item.html">
 <link rel="import" href="chrome://bookmarks/shared_style.html">
@@ skipping 37 matching lines @@
     </dialog>
     <dialog is="cr-dialog" id="editBookmark">
       <div class="title">$i18n{editBookmarkTitle}</div>
       <div class="body">
         <paper-input always-float-label id="name"
             label="$i18n{editDialogNameInput}"
             value="{{menuItem_.title}}">
         </paper-input>
         <paper-input always-float-label id="url"
             label="$i18n{editDialogUrlInput}"
-            value="{{menuItem_.url}}">
+            value="{{menuItem_.url}}"
+            hidden$="[[hideUrlInput_]]">
         </paper-input>
       </div>
       <div class="button-container">
         <paper-button class="cancel-button" on-tap="onCancelEditTap_">
           $i18n{cancelEdit}
         </paper-button>
         <paper-button class="action-button" on-tap="onSaveEditTap_">
           $i18n{saveEdit}
         </paper-button>
       </div>
     </dialog>
     <div id="bookmarksCard" hidden$="[[isEmptyList_(displayedList.length)]]">
       <template is="dom-repeat" items="[[displayedList]]" as="item">
         <bookmarks-item item="[[item]]"></bookmarks-item>
       </template>
     </div>
     <div class="centered-message"
         hidden$="[[!isEmptyList_(displayedList.length)]]">
       [[emptyListMessage_(searchTerm)]]
     </div>
   </template>
   <script src="chrome://bookmarks/list.js"></script>
 </dom-module>