[Suggestions] Remove TreeNode.getSuggestionAt() in favor of a visitor.

chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/ActionItem.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 android.view.View;
 
 import org.chromium.base.VisibleForTesting;
 import org.chromium.chrome.R;
@@ skipping 29 matching lines @@
         return ItemViewType.ACTION;
     }
 
     @Override
     protected void onBindViewHolder(NewTabPageViewHolder holder) {
         assert holder instanceof ViewHolder;
         mSuggestionsRanker.rankActionItem(this, mParentSection);
         ((ViewHolder) holder).onBindViewHolder(this);
     }
 
+    @Override
+    public void visitOptionalItem(NodeVisitor visitor) {
+        visitor.visitActionItem(mCategoryInfo.getAdditionalAction());
+    }
+
     @CategoryInt
     public int getCategory() {
         return mCategoryInfo.getCategory();
     }
 
     public void setPerSectionRank(int perSectionRank) {
         mPerSectionRank = perSectionRank;
     }
 
     public int getPerSectionRank() {
@@ skipping 48 matching lines @@
                 }
             });
         }
 
         public void onBindViewHolder(ActionItem item) {
             super.onBindViewHolder();
             mActionListItem = item;
         }
     }
 }