Fix several element properties in serialization.

pkg/compiler/lib/src/resolution/member_impl.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 dart2js.resolution.compute_members;
 
 class DeclaredMember implements Member {
   final Name name;
   final Element element;
   final InterfaceType declarer;
@@ skipping 120 matching lines @@
 
   Member get implementation => this;
 
   DartType get type => declaration.type.substByContext(instance);
 
   FunctionType get functionType {
     return declaration.functionType.substByContext(instance);
   }
 
   DeclaredMember inheritFrom(InterfaceType newInstance) {
-    assert(() {
+    assert(invariant(declaration.element, () {
       // Assert that if [instance] contains type variables, then these are
       // defined in the declaration of [newInstance] and will therefore be
       // substituted into the context of [newInstance] in the created member.
       ClassElement contextClass = Types.getClassContext(instance);
       return contextClass == null || contextClass == newInstance.element;
-    });
+    }, message: () {
+      return "Context mismatch: Context class "
+          "${Types.getClassContext(instance)} from $instance does match "
+          "the new instance $newInstance.";
+    }));
     return _newInheritedMember(newInstance);
   }
 
   InheritedMember _newInheritedMember(InterfaceType newInstance) {
     return new InheritedMember(
         declaration, instance.substByContext(newInstance));
   }
 
   Iterable<Member> get declarations => <Member>[this];
 
   int get hashCode => declaration.hashCode + 17 * instance.hashCode;
 
   bool operator ==(other) {
     if (other is! InheritedMember) return false;
     return declaration == other.declaration && instance == other.instance;
   }
 
   void printOn(StringBuffer sb, DartType type) {
     declaration.printOn(sb, type);
     sb.write(' inherited from $instance');
   }
 
   String toString() {
     StringBuffer sb = new StringBuffer();
-    printOn(sb, instance);
+    printOn(sb, type);
     return sb.toString();
   }
 }
 
 class InheritedAbstractMember extends InheritedMember {
   final DeclaredMember implementation;
 
   InheritedAbstractMember(
       DeclaredMember declaration, InterfaceType instance, this.implementation)
       : super(declaration, instance);
@@ skipping 54 matching lines @@
 
   bool get isGetter => false;
 
   bool get isMethod => false;
 
   bool get isMalformed => true;
 
   String toString() => "erroneous member '$name' synthesized "
       "from ${inheritedMembers}";
 }