Perform type inference on constructor field initializer expressions.

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

 // Copyright (c) 2016, 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.
 
 library fasta.body_builder;
 
 import 'package:kernel/ast.dart'
     hide InvalidExpression, InvalidInitializer, InvalidStatement;
 
 import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
@@ skipping 3163 matching lines @@
                 .withArguments(name),
             builder.charOffset);
         Builder constructor =
             library.loader.getDuplicatedFieldInitializerError();
         return buildInvalidInitializer(
             new Throw(buildStaticInvocation(constructor.target,
                 new Arguments(<Expression>[new StringLiteral(name)]),
                 charOffset: offset)),
             offset);
       } else {
-        return new FieldInitializer(builder.field, expression)
+        return new KernelFieldInitializer(builder.field, expression)
           ..fileOffset = offset
           ..isSynthetic = isSynthetic;
       }
     } else {
       return buildInvalidInitializer(
           deprecated_buildCompileTimeError(
               "'$name' isn't an instance field of this class.", offset),
           offset);
     }
   }
@@ skipping 605 matching lines @@
       return AsyncMarker.Async;
     } else {
       assert(identical(starToken.stringValue, "*"));
       return AsyncMarker.AsyncStar;
     }
   } else {
     return unhandled(asyncToken.lexeme, "asyncMarkerFromTokens",
         asyncToken.charOffset, null);
   }
 }