Prepare for improved error recovery from compile-time errors.

pkg/kernel/lib/core_types.dart

Index: pkg/kernel/lib/core_types.dart
diff --git a/pkg/kernel/lib/core_types.dart b/pkg/kernel/lib/core_types.dart
index 31df9490f82d39d7670279a6d0bfc1d7b5c60fc7..eeb3700757792eb236aa086361414990f08c8251 100644
--- a/pkg/kernel/lib/core_types.dart
+++ b/pkg/kernel/lib/core_types.dart
@@ -61,6 +61,8 @@ class CoreTypes {
   Procedure _listFromConstructor;
   Procedure _printProcedure;
   Procedure _identicalProcedure;
+  Constructor _constantExpressionErrorDefaultConstructor;
+  Constructor _compileTimeErrorDefaultConstructor;
 
   Class _internalSymbolClass;
 
@@ -255,4 +257,14 @@ class CoreTypes {
   Class get typeClass {
     return _typeClass ??= _index.getClass('dart:core', 'Type');
   }
+
+  Constructor get constantExpressionErrorDefaultConstructor {
+    return _constantExpressionErrorDefaultConstructor ??=
+        _index.getMember('dart:core', '_ConstantExpressionError', '');
+  }
+
+  Constructor get compileTimeErrorDefaultConstructor {
+    return _compileTimeErrorDefaultConstructor ??=
+        _index.getMember('dart:core', '_CompileTimeError', '');
+  }
 }