Emit a compile-time error when the name of a variable is referenced in the

sdk/lib/_internal/compiler/implementation/resolution/members.dart

 // Copyright (c) 2012, 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.
 
 part of resolution;
 
 abstract class TreeElements {
   Element get currentElement;
   Set<Node> get superUses;
 
@@ skipping 3740 matching lines @@
 
   VariableDefinitionsVisitor(Compiler compiler,
                              this.definitions, this.resolver, this.kind)
       : super(compiler) {
     variables = new VariableListElementX.node(
         definitions, ElementKind.VARIABLE_LIST, resolver.enclosingElement);
   }
 
   SourceString visitSendSet(SendSet node) {
     assert(node.arguments.tail.isEmpty); // Sanity check
-    resolver.visit(node.arguments.head);
+    Identifier identifier = node.selector;
+    SourceString name = identifier.source;
+    VariableDefinitionScope scope =
+        new VariableDefinitionScope(resolver.scope, name);
+    resolver.visitIn(node.arguments.head, scope);
+    if (scope.variableReferencedInInitializer) {
+      resolver.error(identifier, MessageKind.REFERENCE_IN_INITIALIZATION,
+                     {'variableName': name.toString()});
+    }
     return visit(node.selector);
   }
 
   SourceString visitIdentifier(Identifier node) {
     // The variable is initialized to null.
     resolver.world.registerInstantiatedClass(compiler.nullClass,
                                              resolver.mapping);
     return node.source;
   }
 
@@ skipping 394 matching lines @@
     return e;
   }
 
   /// Assumed to be called by [resolveRedirectingFactory].
   Element visitReturn(Return node) {
     Node expression = node.expression;
     return finishConstructorReference(visit(expression),
                                       expression, expression);
   }
 }