Fix unit test failure

Change-Id: Ib5e831e46aee395833af5ac4829f7da0a5e6282c

Author: jerryshao

core/src/main/scala/org/apache/spark/deploy/SparkSubmit.scala

@@ -485,12 +485,17 @@ object SparkSubmit extends CommandLineUtils {
 
     // In client mode, launch the application main class directly
     // In addition, add the main application jar and any added jars (if any) to the classpath
+    // Also add the main application jar and any added jars to classpath in case yarn#client
+    // requires these jars.
     if (deployMode == CLIENT || isYarnCluster) {
       childMainClass = args.mainClass
       if (isUserJar(args.primaryResource)) {
         childClasspath += args.primaryResource
       }
       if (args.jars != null) { childClasspath ++= args.jars.split(",") }
+    }
+
+    if (deployMode == CLIENT) {
       if (args.childArgs != null) { childArgs ++= args.childArgs }
     }