Introduce ui.dll / libui.so for the component build.

ui/base/view_prop.h

 // Copyright (c) 2011 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_BASE_VIEW_PROP_H_
 #define UI_BASE_VIEW_PROP_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "ui/gfx/native_widget_types.h"
+#include "ui/ui_api.h"
 
 namespace ui {
 
 // ViewProp maintains a key/value pair for a particular view. ViewProp is
 // designed as a replacement for the Win32's SetProp, but does not make use of
 // window manager memory. ViewProp shares similar semantics as SetProp, the
 // value for a particular view/key pair comes from the last ViewProp created.
-class ViewProp {
+class UI_API ViewProp {
  public:
   // Associates data with a view/key pair. If a ViewProp has already been
   // created for the specified pair |data| replaces the current value.
   //
   // ViewProp does *not* make a copy of the char*, the pointer is used for
   // sorting.
   ViewProp(gfx::NativeView view, const char* key, void* data);
   ~ViewProp();
 
   // Returns the value associated with the view/key pair, or NULL if there is
   // none.
   static void* GetValue(gfx::NativeView view, const char* key);
 
   // Returns the key.
   const char* Key() const;
 
  private:
   class Data;
 
   // Stores the actual data.
   scoped_refptr<Data> data_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewProp);
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_VIEW_PROP_H_