Fix for bug 14666 ("Running this JavaToJavaScript test causes

apprunner to crash."), fix contributed by
jeff.dyer@compilercompany.com, r=drapeau@eng.sun.com. Checks whether
there's a current valid context; if there's no context, don't bother
checking if an exception is pending on that context.

js/src/liveconnect/jsj_JSObject.c

@@ -445,7 +445,7 @@ throw_any_pending_js_error_as_a_java_exception(JSJavaThreadState *jsj_env)
 
     cx = jsj_env->cx;
     /* Get the pending JS exception if it exists */
-    if (JS_IsExceptionPending(cx)) {
+    if (cx&&JS_IsExceptionPending(cx)) {
         if (!JS_GetPendingException(cx, &pending_exception))
             goto out_of_memory;