DATAES-985 - Add builder method for track_total_hits to NativeSearchQueryBuilder.

Original PR: spring-projects#569

Author: sothawo

src/main/java/org/springframework/data/elasticsearch/core/query/NativeSearchQueryBuilder.java

@@ -67,6 +67,7 @@ public class NativeSearchQueryBuilder {
 	@Nullable private IndicesOptions indicesOptions;
 	@Nullable private String preference;
 	@Nullable private Integer maxResults;
+	@Nullable private Boolean trackTotalHits;
 
 	public NativeSearchQueryBuilder withQuery(QueryBuilder queryBuilder) {
 		this.queryBuilder = queryBuilder;
@@ -173,6 +174,14 @@ public NativeSearchQueryBuilder withMaxResults(Integer maxResults) {
 		return this;
 	}
 
+	/**
+	 * @since 4.2
+	 */
+	public NativeSearchQueryBuilder withTrackTotalHits(Boolean trackTotalHits) {
+		this.trackTotalHits = trackTotalHits;
+		return this;
+	}
+
 	public NativeSearchQuery build() {
 
 		NativeSearchQuery nativeSearchQuery = new NativeSearchQuery(queryBuilder, filterBuilder, sortBuilders,
@@ -233,6 +242,8 @@ public NativeSearchQuery build() {
 			nativeSearchQuery.setMaxResults(maxResults);
 		}
 
+		nativeSearchQuery.setTrackTotalHits(trackTotalHits);
+
 		return nativeSearchQuery;
 	}
 }