[NTP Snippets] Fill space below the last snippet if necessary

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

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/NewTabPageListItem.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/NewTabPageListItem.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/NewTabPageListItem.java
index d3ede56f60e33858686266f80d4ba09ef27cf8ea..98d34c378478f6dbe87dc35efc21baec33a3a844 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/NewTabPageListItem.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/NewTabPageListItem.java
@@ -17,7 +17,7 @@
      * @see Adapter#getItemViewType(int)
      * @see NewTabPageListItem#getType()
      */
-    @IntDef({VIEW_TYPE_ABOVE_THE_FOLD, VIEW_TYPE_HEADER, VIEW_TYPE_SNIPPET})
+    @IntDef({VIEW_TYPE_ABOVE_THE_FOLD, VIEW_TYPE_HEADER, VIEW_TYPE_SNIPPET, VIEW_TYPE_PADDING})
     @Retention(RetentionPolicy.SOURCE)
     public @interface ViewType {}
 
@@ -39,6 +39,12 @@
      */
     public static final int VIEW_TYPE_SNIPPET = 3;
 
+   /**
+     * View type for a {@link PaddingListItem} used to provide padding at the end of the list.
+     * @see Adapter#getItemViewType(int)
+     */
+    public static final int VIEW_TYPE_PADDING = 4;
+
     /**
       * Returns the type ({@link ViewType}) of this list item. This is so we can
       * distinguish between different elements that are held in a single RecyclerView holder.