[ntp4] Include a helper link for importing bookmarks if the user doesn't have any.

chrome/browser/resources/ntp4/bookmarks_page.js

Index: chrome/browser/resources/ntp4/bookmarks_page.js
===================================================================
--- chrome/browser/resources/ntp4/bookmarks_page.js	(revision 99893)
+++ chrome/browser/resources/ntp4/bookmarks_page.js	(working copy)
@@ -300,6 +300,9 @@
       } else {
         wrapper.hidden = true;
       }
+
+      if (this.id === ROOT_NODE_ID && !tile_count)
+        this.showImportPromo_();
     },
 
     /**
@@ -368,6 +371,8 @@
     bookmarkNodeAdded: function(id, bookmark, fromCurrentPage) {
       if (this.importing) return;
       if (this.currentlyInFolder_(bookmark.parentId)) {
+        // Hide the import promo if it exists.
+        this.hideImportPromo_();
         // If source of the add came from this page, show an animated insertion,
         // otherwise just quietly do it.
         this.addTileAt(new Bookmark(bookmark), bookmark.index, fromCurrentPage);
@@ -543,6 +548,28 @@
     },
 
     /**
+     * Show the 'Import bookmarks' promo

[Evan Stade, 2011/09/07 19:16:18]

.

[csilv, 2011/09/07 19:29:59]

Done.

+     * @private
+     */
+    showImportPromo_: function() {
+      var importTemplate = $('bookmarks-import-data-link-template');
+      var importWrapper = importTemplate.cloneNode(true);
+      importWrapper.id = '';
+      importWrapper.hidden = false;
+      this.querySelector('.tile-page-content').appendChild(importWrapper);
+    },
+
+    /**
+     * Hide the 'Import bookmarks' promo

[Evan Stade, 2011/09/07 19:16:18]

.

[csilv, 2011/09/07 19:29:59]

Done.

+     * @private
+     */
+    hideImportPromo_: function() {
+      var wrapper = this.querySelector('.bookmarks-import-data-link-wrapper');
+      if (wrapper)
+        wrapper.parentNode.removeChild(wrapper);
+    },
+
+    /**
      * Create a bookmark from a title/url.
      * @param {!string} parentId Stringified int64 of the parent node's ID.
      * @param {number} index Sibling relative index, i.e. 3rd on this level.