Cleans up gyp file for views example and removes duplicate code

ui/views/controls/table/table_grouper.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_CONTROLS_TABLE_TABLE_GROUPER_H_
 #define UI_VIEWS_CONTROLS_TABLE_TABLE_GROUPER_H_
 
+#include "ui/views/views_export.h"
+
 namespace views {
 
-struct GroupRange {
+struct VIEWS_EXPORT GroupRange {
   int start;
   int length;
 };
 
 // TableGrouper is used by TableView to group a set of rows and treat them
 // as one. Rows that fall in the same group are selected together and sorted
 // together.
-class TableGrouper {
+class VIEWS_EXPORT TableGrouper {
  public:
   virtual void GetGroupRange(int model_index, GroupRange* range) = 0;
 
  protected:
   virtual ~TableGrouper() {}
 };
 
 }
 
 #endif  // UI_VIEWS_CONTROLS_TABLE_GROUP_TABLE_VIEW_H_