Remove implicit dependencies.

dart/pkg/compiler/lib/src/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 {
   AnalyzableElement get analyzedElement;
   Iterable<Node> get superUses;
 
@@ skipping 927 matching lines @@
       element.supertypeLoadState = STATE_DONE;
       element.resolutionState = STATE_DONE;
       // TODO(johnniwinther): Check matching type variables and
       // empty extends/implements clauses.
     }
   }
 
   void _postProcessClassElement(BaseClassElementX element) {
     for (MetadataAnnotation metadata in element.metadata) {
       metadata.ensureResolved(compiler);
-      if (!element.isProxy &&
-          metadata.constant.value == compiler.proxyConstant) {
-        element.isProxy = true;
+      if (!element.isProxy) {
+        ConstantExpression constantExpression = metadata.constant;
+        if (constantExpression != null) {
+          ConstantValue constant = constantExpression.value;
+          if (constant.isConstructedObject) {
+            ObjectConstantValue object = constant;
+            if (object.type.element == compiler.proxyClass) {
+              element.isProxy = true;
+            }
+          }
+        }
       }
     }
 
     // Force resolution of metadata on non-instance members since they may be
     // inspected by the backend while emitting. Metadata on instance members is
     // handled as a result of processing instantiated class members in the
     // enqueuer.
     // TODO(ahe): Avoid this eager resolution.
     element.forEachMember((_, Element member) {
       if (!member.isInstanceMember) {
@@ skipping 4092 matching lines @@
 }
 
 /// The result for the resolution of the `assert` method.
 class AssertResult implements ResolutionResult {
   const AssertResult();
 
   Element get element => null;
 
   String toString() => 'AssertResult()';
 }