Simplify Region.hasExtensionType

BauSystem_Main/src/de/steamwar/bausystem/region/Region.java

@@ -216,11 +216,14 @@ public class Region {
     }
 
     public boolean hasExtensionType(RegionType regionType) {
+        if (!hasType(regionType)) {
+            return false;
+        }
         switch (regionType) {
             case BUILD:
-                return prototype != null && prototype.getBuild() != null && prototype.getBuild().isExtensionRegistered();
+                return prototype.getBuild().isExtensionRegistered();
             case TESTBLOCK:
-                return prototype != null && prototype.getTestblock() != null && prototype.getTestblock().isExtensionRegistered();
+                return prototype.getTestblock().isExtensionRegistered();
             default:
             case NORMAL:
                 return false;