SPARK-2766: ScalaReflectionSuite throw an llegalArgumentException in JDK 6

Author: GuoQiang Li <witgo@qq.com>

Closes #1683 from witgo/SPARK-2766 and squashes the following commits:

d0db00c [GuoQiang Li] ScalaReflectionSuite  throw an llegalArgumentException in JDK 6

sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/ScalaReflectionSuite.scala

@@ -182,7 +182,7 @@ class ScalaReflectionSuite extends FunSuite {
     assert(DecimalType === typeOfObject(BigDecimal("1.7976931348623157E318")))
 
     // TimestampType
-    assert(TimestampType === typeOfObject(java.sql.Timestamp.valueOf("2014-7-25 10:26:00")))
+    assert(TimestampType === typeOfObject(java.sql.Timestamp.valueOf("2014-07-25 10:26:00")))
 
     // NullType
     assert(NullType === typeOfObject(null))