Test case DecimalFormat failure with leading 0.

Bug: 27855939
(cherry pick from commit 36a721bfd48e3416033ed62b549090f95ee0b90d)

Change-Id: I2fad00124684439cd811cca5e45738f76c47950d
diff --git a/luni/src/test/java/libcore/java/text/DecimalFormatTest.java b/luni/src/test/java/libcore/java/text/DecimalFormatTest.java
index 0eae20a..2b8b566 100644
--- a/luni/src/test/java/libcore/java/text/DecimalFormatTest.java
+++ b/luni/src/test/java/libcore/java/text/DecimalFormatTest.java
@@ -283,6 +283,13 @@
         assertEquals(expected, numberFormat.format(2.01));
     }
 
+    // http://b/27855939
+    public void testBug27855939() {
+        DecimalFormat df = new DecimalFormat("00");
+        assertEquals("01", df.format(BigDecimal.ONE));
+        assertEquals("00", df.format(BigDecimal.ZERO));
+    }
+
     // Confirm the currency symbol used by a format is determined by the locale of the format
     // not the current default Locale.
     public void testSetCurrency_symbolOrigin() {