Track context menu creation for suggestions.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticleViewHolder.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticleViewHolder.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticleViewHolder.java
index c57fefbc2ba164c832d532858f276db52581578e..7b25f6814d025d243768e504350e9c4fd5727157 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticleViewHolder.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetArticleViewHolder.java
@@ -147,6 +147,11 @@ public class SnippetArticleViewHolder
     }
 
     @Override
+    public void onContextMenuCreated() {
+        mNewTabPageManager.trackSnippetMenuOpened(mArticle);
+    }
+
+    @Override
     protected Delegate getContextMenuDelegate() {
         return this;
     }