JDK 9 RFR of 8160215: jdk/test/java/io/Reader/ReaderBulkReadContract.java should clean up better

[Brian Burkhalter]

Please review at your convenience.

Issue:  https://bugs.openjdk.java.net/browse/JDK-8160215
Diff:

--- a/test/java/io/Reader/ReaderBulkReadContract.java
+++ b/test/java/io/Reader/ReaderBulkReadContract.java
@@ -148,7 +148,8 @@
 
     private static File createTempFileWithContents(String contents) {
         try {
-            File file = File.createTempFile("ReaderContract", "");
+            File testDir = new File(System.getProperty("test.dir", "."));
+            File file = File.createTempFile("ReaderContract", "", testDir);
             try (FileWriter w = new FileWriter(file)) {
                 w.write(contents);

Summary: Create temporary files in the test scratch directory instead of in the 
default temporary file directory.

Thanks,

Brian