Compute initial values for registered custom properties.

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 65 matching lines @@
     ViewportSize(double width, double height) : m_size(width, height) {}
     explicit ViewportSize(const LayoutViewItem&);
 
     double width() const { return m_size.width(); }
     double height() const { return m_size.height(); }
 
    private:
     DoubleSize m_size;
   };
 
-  CSSToLengthConversionData() {}
+  CSSToLengthConversionData() : m_style(nullptr), m_zoom(1) {}
   CSSToLengthConversionData(const ComputedStyle*,
                             const FontSizes&,
                             const ViewportSize&,
                             float zoom);
   CSSToLengthConversionData(const ComputedStyle* currStyle,
                             const ComputedStyle* rootStyle,
                             const LayoutViewItem&,
                             float zoom);
 
   float zoom() const { return m_zoom; }
@@ skipping 25 matching lines @@
  private:
   const ComputedStyle* m_style;
   FontSizes m_fontSizes;
   ViewportSize m_viewportSize;
   float m_zoom;
 };
 
 }  // namespace blink
 
 #endif