Revert "back out earlier #458 fix"

This reverts commit a45edd78.

h2/src/main/org/h2/expression/Function.java

@@ -1880,6 +1880,7 @@ public class Function extends Expression implements FunctionCall {
         default:
             break;
         }
+        calendar = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
         calendar.setTimeInMillis(t1);
         int year1 = calendar.get(Calendar.YEAR);
         int month1 = calendar.get(Calendar.MONTH);

h2/src/test/org/h2/test/testScript.sql

@@ -9935,12 +9935,6 @@ select datediff('year', timestamp '2003-12-01 10:20:30.0', timestamp '2004-12-01
 > 1
 > rows: 1
 
-select datediff('yy', timestamp '2002-12-31 23:59:59.0', timestamp '2003-01-01 13:00:00.0') d1 from test;
-  > D1
-  > --
- > 0
- > rows: 1
-
 select datediff('mm', timestamp '2003-11-01 10:20:30.0', timestamp '2004-01-01 10:00:00.0') d2 from test;
 > D2
 > --