Add type inference for assignment to local variables.

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 '../fasta_codes.dart'
     show FastaMessage, codeExpectedButGot, codeExpectedFunctionBody;
 
 import '../parser/parser.dart'
@@ skipping 3082 matching lines @@
   }
 
   Expression buildNullAwareAssignment(Expression value, DartType type,
       {bool voidContext: false}) {
     return makeInvalidWrite(value);
   }
 
   Expression buildCompoundAssignment(Name binaryOperator, Expression value,
       {int offset: TreeNode.noOffset,
       bool voidContext: false,
-      Procedure interfaceTarget}) {
+      Procedure interfaceTarget,
+      bool isPreIncDec: false}) {
     return makeInvalidWrite(value);
   }
 
   Expression buildPrefixIncrement(Name binaryOperator,
       {int offset: TreeNode.noOffset,
       bool voidContext: false,
       Procedure interfaceTarget}) {
     return makeInvalidWrite(null);
   }
 
@@ skipping 359 matching lines @@
     if (starToken == null) {
       return AsyncMarker.Async;
     } else {
       assert(identical(starToken.stringValue, "*"));
       return AsyncMarker.AsyncStar;
     }
   } else {
     return internalError("Unknown async modifier: $asyncToken");
   }
 }