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

ui/gfx/canvas_direct2d.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_GFX_CANVAS_DIRECT2D_H_
 #define UI_GFX_CANVAS_DIRECT2D_H_
 #pragma once
 
 #include <d2d1.h>
 
 #include <stack>
 
 #include "base/win/scoped_comptr.h"
 #include "ui/gfx/canvas.h"
 
 namespace gfx {
 
-class CanvasDirect2D : public Canvas {
+class UI_API CanvasDirect2D : public Canvas {
  public:
   // Creates an empty Canvas.
   explicit CanvasDirect2D(ID2D1RenderTarget* rt);
   virtual ~CanvasDirect2D();
 
   // Retrieves the application's D2D1 Factory.
   static ID2D1Factory* GetD2D1Factory();
 
   // Overridden from Canvas:
   virtual void Save();
@@ skipping 76 matching lines @@
     int clip_count;
   };
   std::stack<RenderState> state_;
 
   DISALLOW_COPY_AND_ASSIGN(CanvasDirect2D);
 };
 
 }  // namespace gfx;
 
 #endif  // UI_GFX_CANVAS_DIRECT2D_H_