fixed order in check (prefix only appears on jenkins not when I run unit tests locally)

Author: kmader

core/src/test/scala/org/apache/spark/FileSuite.scala

@@ -245,7 +245,7 @@ class FileSuite extends FunSuite with LocalSparkContext {
     val (infile: String, indata: PortableDataStream) = inRdd.first
 
     // Try reading the output back as an object file
-    assert(outFileName.contains(infile)) // a prefix may get added
+    assert(infile.contains(outFileName)) // a prefix may get added
     assert(indata.toArray === testOutput)
   }