[Android NTP] Move suggestions in SuggestionSection into a separate TreeNode.

chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticle.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticle.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticle.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticle.java
index de06a3c3608cffc48ac8556c941f21e3d5050ecf..5f79c18d8e40b6df70e7dddee296b5f3302fb0b3 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticle.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticle.java
@@ -5,15 +5,12 @@ package org.chromium.chrome.browser.ntp.snippets;
 
 import android.graphics.Bitmap;
 
-import org.chromium.chrome.browser.ntp.cards.ItemViewType;
-import org.chromium.chrome.browser.ntp.cards.Leaf;
-import org.chromium.chrome.browser.ntp.cards.NewTabPageViewHolder;
 import org.chromium.chrome.browser.ntp.snippets.ContentSuggestionsCardLayout.ContentSuggestionsCardLayoutEnum;
 
 /**
  * Represents the data for an article card on the NTP.
  */
-public class SnippetArticle extends Leaf {
+public class SnippetArticle {
     /** The category of this article. */
     public final int mCategory;
 
@@ -88,25 +85,6 @@ public class SnippetArticle extends Leaf {
         return mCategory ^ mIdWithinCategory.hashCode();
     }
 
-    @Override
-    @ItemViewType
-    public int getItemViewType() {
-        return ItemViewType.SNIPPET;
-    }
-
-    @Override
-    protected void onBindViewHolder(NewTabPageViewHolder holder) {
-        assert holder instanceof SnippetArticleViewHolder;
-        ((SnippetArticleViewHolder) holder).onBindViewHolder(this);
-    }
-
-    @Override
-    public SnippetArticle getSuggestionAt(int position) {
-        if (position != 0) throw new IndexOutOfBoundsException();
-
-        return this;
-    }
-
     /**
      * Returns this article's thumbnail as a {@link Bitmap}. Can return {@code null} as it is
      * initially unset.