Bug #1343: Only closed projects in company view perspective are displayed in grey

The tasks inside closed projects are now being shown as usual, and not marked
as closed projects in the company view.

FEA: ItEr76S04BugFixing

ganttzk/src/main/java/org/zkoss/ganttz/TaskComponent.java

@@ -222,7 +222,7 @@ public class TaskComponent extends Div implements AfterCompose {
             cssClass += task.isLimitingAndHasDayAssignments() ? " limiting-assigned "
                     : " limiting-unassigned ";
         }
-        if (task.belongsClosedProject()) {
+        if (task.isRoot() && task.belongsClosedProject()) {
             cssClass += " project-closed ";
         }
         return cssClass;