Add type inference for invalid constructor initializers.

pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// This file declares a "shadow hierarchy" of concrete classes which extend
 /// the kernel class hierarchy, adding methods and fields needed by the
 /// BodyBuilder.
 ///
 /// Instances of these classes may be created using the factory methods in
 /// `ast_factory.dart`.
@@ skipping 1001 matching lines @@
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
     typeNeeded =
         inferrer.listener.intLiteralEnter(this, typeContext) || typeNeeded;
     var inferredType = typeNeeded ? inferrer.coreTypes.intClass.rawType : null;
     inferrer.listener.intLiteralExit(this, inferredType);
     return inferredType;
   }
 }
 
+/// Concrete shadow object representing an invalid initializer in kernel form.
+class KernelInvalidInitializer extends LocalInitializer
+    implements KernelInitializer {
+  KernelInvalidInitializer(VariableDeclaration variable) : super(variable);
+
+  @override
+  void _inferInitializer(KernelTypeInferrer inferrer) {
+    inferrer.listener.invalidInitializerEnter(this);
+    inferrer.inferExpression(variable.initializer, null, false);
+    inferrer.listener.invalidInitializerExit(this);
+  }
+}
+
 /// Concrete shadow object representing a non-inverted "is" test in kernel form.
 class KernelIsExpression extends IsExpression implements KernelExpression {
   KernelIsExpression(Expression operand, DartType type) : super(operand, type);
 
   @override
   void _collectDependencies(KernelDependencyCollector collector) {
     // No inference dependencies.
   }
 
   @override
@@ skipping 1430 matching lines @@
   accept(v) => unsupported("accept", -1, null);
 
   accept1(v, arg) => unsupported("accept1", -1, null);
 
   getStaticType(types) => unsupported("getStaticType", -1, null);
 
   transformChildren(v) => unsupported("transformChildren", -1, null);
 
   visitChildren(v) => unsupported("visitChildren", -1, null);
 }