fix compile; add doc

processing/src/main/java/org/apache/druid/query/FrameBasedInlineDataSource.java

@@ -103,7 +103,7 @@ public class FrameBasedInlineDataSource implements DataSource
               .collect(Collectors.toList());
 
           return Sequences.simple(
-              () -> new Iterator<>()
+              () -> new Iterator<Object[]>()
               {
                 @Override
                 public boolean hasNext()

server/src/test/java/org/apache/druid/server/QuerySchedulerTest.java

@@ -666,7 +666,7 @@ public class QuerySchedulerTest
   {
     return new LazySequence<>(() -> {
       return new BaseSequence<>(
-          new BaseSequence.IteratorMaker<>()
+          new BaseSequence.IteratorMaker<Integer, Iterator<Integer>>()
           {
             @Override
             public Iterator<Integer> make()

sql/src/main/java/org/apache/druid/sql/calcite/planner/DruidRelFieldTrimmer.java

@@ -99,6 +99,9 @@ public class DruidRelFieldTrimmer extends RelFieldTrimmer
     return result(input, mapping);
   }
 
+  /**
+   * Should be unnecesarry in versions having CALCITE-6715
+   */
   public TrimResult trimFields(LogicalCorrelate correlate,
       ImmutableBitSet fieldsUsed,
       Set<RelDataTypeField> extraFields)