Remove DateException and obsolete DateUtils functions.

These functions are deprecated and no longer used.
diff --git a/calendar/Android.mk b/calendar/Android.mk
index fd20dfa..7f9ee0a 100644
--- a/calendar/Android.mk
+++ b/calendar/Android.mk
@@ -10,7 +10,6 @@
 	../core/java/android/pim/ICalendar.java \
 	../core/java/android/pim/RecurrenceSet.java \
 	../core/java/android/pim/ContactsAsyncHelper.java \
-	../core/java/android/pim/DateException.java
 
 include $(BUILD_STATIC_JAVA_LIBRARY)