Roll kernel to latest and add baseline test.

pkg/compiler/lib/src/serialization/modelz.dart

Index: pkg/compiler/lib/src/serialization/modelz.dart
diff --git a/pkg/compiler/lib/src/serialization/modelz.dart b/pkg/compiler/lib/src/serialization/modelz.dart
index a6ba195b090363f29bfb00719689cdb15618fb94..a628cbf376721372e65f5aeb9a8015f0d0b3d615 100644
--- a/pkg/compiler/lib/src/serialization/modelz.dart
+++ b/pkg/compiler/lib/src/serialization/modelz.dart
@@ -1242,6 +1242,9 @@ abstract class ConstructorElementZ extends DeserializedElementZ
   @override
   bool get isExternal => _decoder.getBool(Key.IS_EXTERNAL);
 
+  @override
+  bool get isDefaultConstructor => false;
+
   ConstantConstructor get constantConstructor {
     if (isConst && _constantConstructor == null) {
       ObjectDecoder data =
@@ -1320,6 +1323,9 @@ class DefaultConstructorElementZ extends ConstructorElementZ {
   bool get isSynthesized => true;
 
   @override
+  bool get isDefaultConstructor => true;
+
+  @override
   ConstructorElement get definingConstructor {
     return enclosingClass.superclass.lookupConstructor('');
   }
@@ -1440,6 +1446,9 @@ class ForwardingConstructorElementZ extends ElementZ
   bool get isClassMember => true;
 
   @override
+  bool get isDefaultConstructor => false;
+
+  @override
   ConstantConstructor get constantConstructor => null;
 
   @override