Revert "[kernel] offsets on direct property get/set"

pkg/kernel/lib/transformations/mixin_full_resolution.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 kernel.transformations.mixin_full_resolution;
 
 import '../ast.dart';
 import '../class_hierarchy.dart';
 import '../clone.dart';
 import '../core_types.dart';
 import '../type_algebra.dart';
@@ skipping 169 matching lines @@
   Procedure _listFrom; // cached
 
   SuperCallResolutionTransformer(
       this.hierarchy, this.coreTypes, this.lookupClass);
 
   TreeNode visit(TreeNode node) => node.accept(this);
 
   visitSuperPropertyGet(SuperPropertyGet node) {
     Member target = hierarchy.getDispatchTarget(lookupClass, node.name);
     if (target != null) {
-      return new DirectPropertyGet(new ThisExpression(), target)
-        ..fileOffset = node.fileOffset;
+      return new DirectPropertyGet(new ThisExpression(), target);
     } else {
       return _callNoSuchMethod(node.name.name, new Arguments.empty(), node,
           isGetter: true, isSuper: true);
     }
   }
 
   visitSuperPropertySet(SuperPropertySet node) {
     Member target =
         hierarchy.getDispatchTarget(lookupClass, node.name, setter: true);
     if (target != null) {
       return new DirectPropertySet(
-          new ThisExpression(), target, visit(node.value))
-        ..fileOffset = node.fileOffset;
+          new ThisExpression(), target, visit(node.value));
     } else {
       // Call has to return right-hand-side.
       VariableDeclaration rightHandSide =
           new VariableDeclaration.forValue(visit(node.value));
       Expression result = _callNoSuchMethod(
           node.name.name, new Arguments([new VariableGet(rightHandSide)]), node,
           isSetter: true, isSuper: true);
       VariableDeclaration call = new VariableDeclaration.forValue(result);
       return new Let(
           rightHandSide, new Let(call, new VariableGet(rightHandSide)));
@@ skipping 155 matching lines @@
           return null;
         }
       }
 
       throw new Exception(
           'Could not find a generative constructor named "${constructor.name}" '
           'in lookup class "${lookupClass.name}"!');
     }
   }
 }