Use new Change#isMerged() method

Change-Id: I78dbfa5c4af65fdf215eb32ccdc1ee09d39f9f6d

src/main/java/com/googlesource/gerrit/plugins/reviewnotes/ExportReviewNotes.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/ExportReviewNotes.java b/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/ExportReviewNotes.java
index ce159b4..06975a0 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/ExportReviewNotes.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/ExportReviewNotes.java
@@ -21,7 +21,6 @@
 import com.google.common.collect.Maps;
 import com.google.common.collect.MultimapBuilder;
 import com.google.gerrit.extensions.restapi.RestApiException;
-import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.notedb.ChangeNotes;
@@ -76,8 +75,7 @@
     try {
       return MultimapBuilder.hashKeys()
           .arrayListValues()
-          .build(
-              notesFactory.create(notes -> notes.getChange().getStatus() == Change.Status.MERGED));
+          .build(notesFactory.create(notes -> notes.getChange().isMerged()));
     } catch (IOException e) {
       stderr.println("Cannot read changes from database " + e.getMessage());
       return ImmutableListMultimap.of();