Update Since Tag for 8.6 (#11256)

client/src/main/java/com/vaadin/client/ui/VAbstractCalendarPanel.java

@@ -941,7 +941,7 @@ public abstract class VAbstractCalendarPanel<R extends Enum<R>>
     /**
      * Returns the value of initialRenderDone
      *
-     * @since
+     * @since 8.6
      */
     public boolean isInitialRenderDone() {
         return initialRenderDone;

client/src/main/java/com/vaadin/client/widget/escalator/RowContainer.java

@@ -238,7 +238,7 @@ public interface RowContainer {
     /**
      * For internal use only. May be removed or replaced in the future.
      *
-     * @since
+     * @since 8.6
      * @return {@code true} if row height calculations have been scheduled
      */
     public boolean isAutodetectingRowHeightLater();

compatibility-client/src/main/java/com/vaadin/v7/client/widget/escalator/RowContainer.java

@@ -230,7 +230,7 @@ public interface RowContainer {
      * Any extra content, such as spacers for the body, should not be included
      * in this count.
      *
-     * @since
+     * @since 8.6
      *
      * @return the actual DOM count of rows
      */