Add type inference for super property gets.

pkg/front_end/lib/src/fasta/kernel/frontend_accessors.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.
 
 /// A library to help transform compounds and null-aware accessors into
 /// let expressions.
 
 import 'package:front_end/src/fasta/kernel/kernel_shadow_ast.dart'
     show
         KernelArguments,
         KernelComplexAssignment,
         KernelConditionalExpression,
         KernelMethodInvocation,
         KernelNullAwarePropertyGet,
         KernelPropertyAssign,
         KernelPropertyGet,
+        KernelSuperPropertyGet,
         KernelThisExpression,
         KernelVariableDeclaration,
         KernelVariableGet;
 
 import 'package:front_end/src/fasta/kernel/utils.dart' show offsetForToken;
 
 import 'package:front_end/src/scanner/token.dart' show Token;
 
 import 'package:front_end/src/fasta/kernel/fasta_accessors.dart'
     show BuilderHelper;
@@ skipping 340 matching lines @@
   Name name;
   Member getter, setter;
 
   SuperPropertyAccessor(
       BuilderHelper helper, this.name, this.getter, this.setter, Token token)
       : super(helper, token);
 
   Expression _makeRead(KernelComplexAssignment complexAssignment) {
     if (getter == null) return makeInvalidRead();
     // TODO(ahe): Use [DirectPropertyGet] when possible.
-    var read = new SuperPropertyGet(name, getter)
+    var read = new KernelSuperPropertyGet(name, getter)
       ..fileOffset = offsetForToken(token);
     complexAssignment?.read = read;
     return read;
   }
 
   Expression _makeWrite(Expression value, bool voidContext,
       KernelComplexAssignment complexAssignment) {
     if (setter == null) return makeInvalidWrite(value);
     // TODO(ahe): Use [DirectPropertySet] when possible.
     var write = new SuperPropertySet(name, value, setter)
@@ skipping 335 matching lines @@
 
 Expression buildIsNull(Expression value, int offset) {
   return makeBinary(value, equalsName, null, new NullLiteral(), offset: offset);
 }
 
 VariableDeclaration makeOrReuseVariable(Expression value) {
   // TODO: Devise a way to remember if a variable declaration was reused
   // or is fresh (hence needs a let binding).
   return new VariableDeclaration.forValue(value);
 }