src/macosx/classes/sun/lwawt/macosx/CPlatformWindow.java

@@ -898,12 +898,10 @@
         long nativePeer = 0L;
         if (platformWindow instanceof CPlatformWindow) {
             nativePeer = ((CPlatformWindow) platformWindow).getContentView().getAWTView();
         } else if (platformWindow instanceof CViewPlatformEmbeddedFrame){
             nativePeer = ((CViewPlatformEmbeddedFrame) platformWindow).getNSViewPtr();
-        } else {
-            throw new IllegalArgumentException("Unsupported platformWindow implementation");
         }
         return nativePeer;
     }
 
     /*************************************************************