[Android NTP] Move suggestion sections into a separate node.

chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/InnerNode.java

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.ntp.cards;
 
 import org.chromium.chrome.browser.ntp.snippets.SnippetArticle;
 
 import java.util.List;
 
@@ skipping 90 matching lines @@
 
     @Override
     public void onItemRangeInserted(TreeNode child, int index, int count) {
         notifyItemRangeInserted(getStartingOffsetForChild(child) + index, count);
     }
 
     @Override
     public void onItemRangeRemoved(TreeNode child, int index, int count) {
         notifyItemRangeRemoved(getStartingOffsetForChild(child) + index, count);
     }
+
+    @Override
+    public void init() {
+        super.init();
+        for (TreeNode child : getChildren()) {
+            child.init();
+        }
+    }
+
+    /**
+     * Helper method for adding a new child node. Notifies about the inserted items and initializes
+     * the child.
+     *
+     * @param child The child node to be added.
+     */
+    protected void didAddChild(TreeNode child) {
+        int count = child.getItemCount();
+        if (count > 0) onItemRangeInserted(child, 0, count);
+        child.init();
+    }
+
+    /**
+     * Helper method for removing a child node. Notifies about the removed items.
+     *
+     * @param child The child node to be removed.
+     */
+    protected void willRemoveChild(TreeNode child) {
+        int count = child.getItemCount();
+        if (count > 0) onItemRangeRemoved(child, 0, count);
+    }
 }