Change core lib, dart2js, and more for new optional parameters syntax

tests/co19/co19-runtime.status

Index: tests/co19/co19-runtime.status
===================================================================
--- tests/co19/co19-runtime.status	(revision 13683)
+++ tests/co19/co19-runtime.status	(working copy)
@@ -3,6 +3,23 @@
 # BSD-style license that can be found in the LICENSE file.
 
 [ $compiler == none && $runtime == vm ]
+# These tests need to be updated to the new Date core lib API, co19 issue 256:
+LibTest/core/Date/Date.fromMillisecondsSinceEpoch_A01_t01: Fail
+LibTest/core/Date/Date.fromMillisecondsSinceEpoch_A01_t02: Fail
+LibTest/core/Date/Date_A01_t04: Fail
+LibTest/core/Date/Date_A01_t05: Fail
+LibTest/core/Date/isUtc_A01_t01: Fail
+LibTest/core/Date/millisecondsSinceEpoch_A01_t01: Fail
+LibTest/core/Date/operator_GE_A01_t01: Fail
+LibTest/core/Date/operator_GT_A01_t01: Fail
+LibTest/core/Date/operator_LE_A01_t01: Fail
+LibTest/core/Date/operator_LT_A01_t01: Fail
+LibTest/core/Date/operator_equality_A01_t01: Fail
+LibTest/core/Date/timeZoneName_A01_t01: Fail
+LibTest/core/Date/timeZoneOffset_A01_t01: Fail
+LibTest/core/Date/toLocal_A01_t01: Fail
+LibTest/core/Date/toUtc_A01_t01: Fail
+
 Language/13_Libraries_and_Scripts/2_Imports_A02_t21: Crash # TODO(vm-team): Please triage this crash.
 Language/13_Libraries_and_Scripts/2_Imports_A02_t22: Crash # TODO(vm-team): Please triage this crash.
 LibTest/isolate/isolate_api/port_A01_t01: Skip # Times out.
@@ -254,7 +271,6 @@
 Language/10_Expressions/30_Type_Cast_A05_t03: Fail # TODO(vm-team): Please triage this failure.
 Language/10_Expressions/30_Type_Cast_A05_t04: Fail # TODO(vm-team): Please triage this failure.
 Language/10_Expressions/30_Type_Cast_A05_t05: Fail # TODO(vm-team): Please triage this failure.
-LibTest/core/Date/Date.fromMillisecondsSinceEpoch_A03_t01: Fail # TODO(vm-team): Please triage this failure.
 
 
 [ $compiler == none && $runtime == vm ]