Implement type inference of constructor invocations in Fasta.

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 79 matching lines @@
 class KernelConstructorInvocation extends ConstructorInvocation
     implements KernelExpression {
   KernelConstructorInvocation(Constructor target, Arguments arguments,
       {bool isConst: false})
       : super(target, arguments, isConst: isConst);
 
   KernelConstructorInvocation.byReference(
       Reference targetReference, Arguments arguments)
       : super.byReference(targetReference, arguments);
 
+  void _forEachArgument(void callback(String name, Expression expression)) {
+    for (var expression in arguments.positional) {
+      callback(null, expression);
+    }
+    for (var namedExpression in arguments.named) {
+      callback(namedExpression.name, namedExpression.value);
+    }
+  }
+
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
-    // TODO(scheglov): implement.
-    return typeNeeded ? const DynamicType() : null;
+    return inferrer.inferConstructorInvocation(
+        typeContext,
+        typeNeeded,
+        fileOffset,
+        target,
+        arguments.types.isEmpty ? null : arguments.types,
+        _forEachArgument, (type) {
+      arguments = new Arguments(arguments.positional,
+          named: arguments.named, types: type.typeArguments);
+    });
   }
 }
 
 /// Shadow object for [DirectMethodInvocation].
 class KernelDirectMethodInvocation extends DirectMethodInvocation
     implements KernelExpression {
   KernelDirectMethodInvocation(
       Expression receiver, Procedure target, Arguments arguments)
       : super(receiver, target, arguments);
 
@@ skipping 773 matching lines @@
       : super(variable, value);
 
   @override
   DartType _inferExpression(
       KernelTypeInferrer inferrer, DartType typeContext, bool typeNeeded) {
     var variable = this.variable as KernelVariableDeclaration;
     return inferrer.inferVariableSet(
         typeContext, typeNeeded, variable._declaredType, value);
   }
 }