[FLINK-8230] [orc] Fix NPEs when reading nested columns.

- fixes NPEs for null-valued structs, lists, and maps
- fixes NPEs for repeating structs, lists, and maps
- adds test for deeply nested data with nulls
- adds test for columns with repeating values

This closes apache#5373.

flink-connectors/flink-orc/src/main/java/org/apache/flink/orc/OrcRowInputFormat.java

@@ -55,7 +55,7 @@
 import java.util.Arrays;
 import java.util.List;
 
-import static org.apache.flink.orc.OrcUtils.fillRows;
+import static org.apache.flink.orc.OrcBatchReader.fillRows;
 
 /**
  * InputFormat to read ORC files.
@@ -128,7 +128,7 @@ public OrcRowInputFormat(String path, TypeDescription orcSchema, Configuration o
 
 		// configure OrcRowInputFormat
 		this.schema = orcSchema;
-		this.rowType = (RowTypeInfo) OrcUtils.schemaToTypeInfo(schema);
+		this.rowType = (RowTypeInfo) OrcBatchReader.schemaToTypeInfo(schema);
 		this.conf = orcConfig;
 		this.batchSize = batchSize;
 

flink-connectors/flink-orc/src/main/java/org/apache/flink/orc/OrcTableSource.java

@@ -127,7 +127,7 @@ private OrcTableSource(String path, TypeDescription orcSchema, Configuration orc
 		this.predicates = predicates;
 
 		// determine the type information from the ORC schema
-		RowTypeInfo typeInfoFromSchema = (RowTypeInfo) OrcUtils.schemaToTypeInfo(this.orcSchema);
+		RowTypeInfo typeInfoFromSchema = (RowTypeInfo) OrcBatchReader.schemaToTypeInfo(this.orcSchema);
 
 		// set return type info
 		if (selectedFields == null) {