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diff --git a/components/newtab/updater.js b/components/newtab/updater.js
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+#ifdef 0
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+#endif
+
+/**
+ * This singleton provides functionality to update the current grid to a new
+ * set of pinned and blocked sites. It adds, moves and removes sites.
+ */
+var gUpdater = {
+  /**
+   * Updates the current grid according to its pinned and blocked sites.
+   * This removes old, moves existing and creates new sites to fill gaps.
+   * @param aCallback The callback to call when finished.
+   */
+  updateGrid: function Updater_updateGrid(aCallback) {
+    let links = gLinks.getLinks().slice(0, gGrid.cells.length);
+
+    // Find all sites that remain in the grid.
+    let sites = this._findRemainingSites(links);
+
+    // Remove sites that are no longer in the grid.
+    this._removeLegacySites(sites, () => {
+      // Freeze all site positions so that we can move their DOM nodes around
+      // without any visual impact.
+      this._freezeSitePositions(sites);
+
+      // Move the sites' DOM nodes to their new position in the DOM. This will
+      // have no visual effect as all the sites have been frozen and will
+      // remain in their current position.
+      this._moveSiteNodes(sites);
+
+      // Now it's time to animate the sites actually moving to their new
+      // positions.
+      this._rearrangeSites(sites, () => {
+        // Try to fill empty cells and finish.
+        this._fillEmptyCells(links, aCallback);
+
+        // Update other pages that might be open to keep them synced.
+        gAllPages.update(gPage);
+      });
+    });
+  },
+
+  /**
+   * Takes an array of links and tries to correlate them to sites contained in
+   * the current grid. If no corresponding site can be found (i.e. the link is
+   * new and a site will be created) then just set it to null.
+   * @param aLinks The array of links to find sites for.
+   * @return Array of sites mapped to the given links (can contain null values).
+   */
+  _findRemainingSites: function Updater_findRemainingSites(aLinks) {
+    let map = {};
+
+    // Create a map to easily retrieve the site for a given URL.
+    gGrid.sites.forEach(function (aSite) {
+      if (aSite)
+        map[aSite.url] = aSite;
+    });
+
+    // Map each link to its corresponding site, if any.
+    return aLinks.map(function (aLink) {
+      return aLink && (aLink.url in map) && map[aLink.url];
+    });
+  },
+
+  /**
+   * Freezes the given sites' positions.
+   * @param aSites The array of sites to freeze.
+   */
+  _freezeSitePositions: function Updater_freezeSitePositions(aSites) {
+    aSites.forEach(function (aSite) {
+      if (aSite)
+        gTransformation.freezeSitePosition(aSite);
+    });
+  },
+
+  /**
+   * Moves the given sites' DOM nodes to their new positions.
+   * @param aSites The array of sites to move.
+   */
+  _moveSiteNodes: function Updater_moveSiteNodes(aSites) {
+    let cells = gGrid.cells;
+
+    // Truncate the given array of sites to not have more sites than cells.
+    // This can happen when the user drags a bookmark (or any other new kind
+    // of link) onto the grid.
+    let sites = aSites.slice(0, cells.length);
+
+    sites.forEach(function (aSite, aIndex) {
+      let cell = cells[aIndex];
+      let cellSite = cell.site;
+
+      // The site's position didn't change.
+      if (!aSite || cellSite != aSite) {
+        let cellNode = cell.node;
+
+        // Empty the cell if necessary.
+        if (cellSite)
+          cellNode.removeChild(cellSite.node);
+
+        // Put the new site in place, if any.
+        if (aSite)
+          cellNode.appendChild(aSite.node);
+      }
+    }, this);
+  },
+
+  /**
+   * Rearranges the given sites and slides them to their new positions.
+   * @param aSites The array of sites to re-arrange.
+   * @param aCallback The callback to call when finished.
+   */
+  _rearrangeSites: function Updater_rearrangeSites(aSites, aCallback) {
+    let options = {callback: aCallback, unfreeze: true};
+    gTransformation.rearrangeSites(aSites, options);
+  },
+
+  /**
+   * Removes all sites from the grid that are not in the given links array or
+   * exceed the grid.
+   * @param aSites The array of sites remaining in the grid.
+   * @param aCallback The callback to call when finished.
+   */
+  _removeLegacySites: function Updater_removeLegacySites(aSites, aCallback) {
+    let batch = [];
+
+    // Delete sites that were removed from the grid.
+    gGrid.sites.forEach(function (aSite) {
+      // The site must be valid and not in the current grid.
+      if (!aSite || aSites.indexOf(aSite) != -1)
+        return;
+
+      batch.push(new Promise(resolve => {
+        // Fade out the to-be-removed site.
+        gTransformation.hideSite(aSite, function () {
+          let node = aSite.node;
+
+          // Remove the site from the DOM.
+          node.parentNode.removeChild(node);
+          resolve();
+        });
+      }));
+    });
+
+    Promise.all(batch).then(aCallback);
+  },
+
+  /**
+   * Tries to fill empty cells with new links if available.
+   * @param aLinks The array of links.
+   * @param aCallback The callback to call when finished.
+   */
+  _fillEmptyCells: function Updater_fillEmptyCells(aLinks, aCallback) {
+    let {cells, sites} = gGrid;
+
+    // Find empty cells and fill them.
+    Promise.all(sites.map((aSite, aIndex) => {
+      if (aSite || !aLinks[aIndex])
+        return null;
+
+      return new Promise(resolve => {
+        // Create the new site and fade it in.
+        let site = gGrid.createSite(aLinks[aIndex], cells[aIndex]);
+
+        // Set the site's initial opacity to zero.
+        site.node.style.opacity = 0;
+
+        // Flush all style changes for the dynamically inserted site to make
+        // the fade-in transition work.
+        window.getComputedStyle(site.node).opacity;
+        gTransformation.showSite(site, resolve);
+      });
+    })).then(aCallback).catch(console.exception);
+  }
+};