Cleans up gyp file for views example and removes duplicate code

ui/views/examples/text_example.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_EXAMPLES_TEXT_EXAMPLE_H_
 #define UI_VIEWS_EXAMPLES_TEXT_EXAMPLE_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_vector.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/controls/combobox/combobox_listener.h"
 #include "ui/views/examples/example_base.h"
 
 namespace views {
 class Checkbox;
 class GridLayout;
 
 namespace examples {
 
 class ExampleComboboxModel;
 
-class TextExample : public ExampleBase,
-                    public ButtonListener,
-                    public ComboboxListener {
+class VIEWS_EXAMPLES_EXPORT TextExample : public ExampleBase,
+                                          public ButtonListener,
+                                          public ComboboxListener {
  public:
   TextExample();
   virtual ~TextExample();
 
   // Overridden from ExampleBase:
   virtual void CreateExampleView(View* container) OVERRIDE;
 
  private:
   // Creates and adds a check box to the layout.
   Checkbox* AddCheckbox(GridLayout* layout, const char* name);
@@ skipping 48 matching lines @@
   // around until destruction time.
   ScopedVector<ExampleComboboxModel> example_combobox_model_;
 
   DISALLOW_COPY_AND_ASSIGN(TextExample);
 };
 
 }  // namespace examples
 }  // namespace views
 
 #endif  // UI_VIEWS_EXAMPLES_TEXT_EXAMPLE_H_