Print errors encountered while writing XML reports

Change-Id: I7fdf9f6989c94a3f0fd3ff93db3426a4d080120f
diff --git a/libcore/luni/src/test/java/com/google/coretests/XmlReportPrinter.java b/libcore/luni/src/test/java/com/google/coretests/XmlReportPrinter.java
index 315371f..edd9a12 100644
--- a/libcore/luni/src/test/java/com/google/coretests/XmlReportPrinter.java
+++ b/libcore/luni/src/test/java/com/google/coretests/XmlReportPrinter.java
@@ -148,6 +148,7 @@
                     try {
                         stream.close();
                     } catch (IOException ignored) {
+                        ignored.printStackTrace();
                     }
                 }
             }
@@ -246,4 +247,4 @@
             return name.hashCode() ^ className.hashCode();
         }
     }
-}
\ No newline at end of file
+}