Adds a gfx_export.h to ui/gfx and converts all code in ui/gfx to

ui/gfx/quad_f.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_GFX_QUAD_F_H_
 #define UI_GFX_QUAD_F_H_
 
 #include <cmath>
 #include <string>
 
-#include "ui/base/ui_export.h"
+#include "ui/gfx/gfx_export.h"
 #include "ui/gfx/point_f.h"
 #include "ui/gfx/rect_f.h"
 
 namespace gfx {
 
 // A Quad is defined by four corners, allowing it to have edges that are not
 // axis-aligned, unlike a Rect.
 class UI_EXPORT QuadF {
  public:
   QuadF() {}
@@ skipping 77 matching lines @@
 
 // Add a vector to a quad, offseting each point in the quad by the vector.
 UI_EXPORT QuadF operator+(const QuadF& lhs, const Vector2dF& rhs);
 // Subtract a vector from a quad, offseting each point in the quad by the
 // inverse of the vector.
 UI_EXPORT QuadF operator-(const QuadF& lhs, const Vector2dF& rhs);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_QUAD_F_H_