Adding wireframe to the shadow map demo.

samples/o3djs/effect.js

Index: samples/o3djs/effect.js
===================================================================
--- samples/o3djs/effect.js	(revision 49133)
+++ samples/o3djs/effect.js	(working copy)
@@ -1310,11 +1310,11 @@
     // help the user get something on the screen. We check to make sure they
     // are not connected to something otherwise we'll get an error.
     var param = material.getParam('lightWorldPos');
-    if (!param.inputConnection) {
+    if (param && !param.inputConnection) {
       param.value = lightPos;
     }
     var param = material.getParam('lightColor');
-    if (!param.inputConnection) {
+    if (param && !param.inputConnection) {
       param.value = [1, 1, 1, 1];
     }
     return true;