Reland of Don't change layout size due to top control show/hide

third_party/WebKit/Source/core/css/CSSToLengthConversionData.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef CSSToLengthConversionData_h
 #define CSSToLengthConversionData_h
 
 #include "core/CoreExport.h"
 #include "core/css/CSSPrimitiveValue.h"
+#include "platform/geometry/DoubleSize.h"
 #include "wtf/Allocator.h"
 #include "wtf/Assertions.h"
 #include "wtf/MathExtras.h"
 #include <limits>
 
 namespace blink {
 
 class ComputedStyle;
 class LayoutView;
 class Font;
@@ skipping 15 matching lines @@
         float ch() const;
     private:
         float m_em;
         float m_rem;
         const Font* m_font;
     };
 
     class ViewportSize {
         DISALLOW_NEW();
     public:
-        ViewportSize() : m_width(0), m_height(0) { }
-        ViewportSize(double width, double height) : m_width(width), m_height(height) { }
+        ViewportSize() { }
+        ViewportSize(double width, double height) : m_size(width, height) { }
         explicit ViewportSize(const LayoutView*);
 
-        double width() const { return m_width; }
-        double height() const { return m_height; }
+        double width() const { return m_size.width(); }
+        double height() const { return m_size.height(); }
     private:
-        double m_width;
-        double m_height;
+        DoubleSize m_size;
     };
 
     CSSToLengthConversionData() { }
     CSSToLengthConversionData(const ComputedStyle*, const FontSizes&, const ViewportSize&, float zoom);
     CSSToLengthConversionData(const ComputedStyle* currStyle, const ComputedStyle* rootStyle, const LayoutView*, float zoom);
 
     float zoom() const { return m_zoom; }
 
     float emFontSize() const { return m_fontSizes.em(); }
     float remFontSize() const;
@@ skipping 23 matching lines @@
 private:
     const ComputedStyle* m_style;
     FontSizes m_fontSizes;
     ViewportSize m_viewportSize;
     float m_zoom;
 };
 
 } // namespace blink
 
 #endif