[Blink] Display images on a dark background

third_party/WebKit/Source/core/html/ImageDocument.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 29 matching lines @@
       const DocumentInit& initializer = DocumentInit()) {
     return new ImageDocument(initializer);
   }
 
   ImageResource* cachedImage();
   HTMLImageElement* imageElement() const { return m_imageElement.get(); }
 
   void windowSizeChanged();
   void imageUpdated();
   void imageClicked(int x, int y);
+  void imageLoaded();
+  void updateImageStyle();
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   explicit ImageDocument(const DocumentInit&);
 
   DocumentParser* createParser() override;
 
   void createDocumentStructure();
 
+  // Calculates how large the div needs to be to properly center the image.
+  int calculateDivWidth();
+
   // These methods are for m_shrinkToFitMode == Desktop.
   void resizeImageToFit();
   void restoreImageSize();
   bool imageFitsInWindow() const;
   bool shouldShrinkToFit() const;
   // Calculates the image size multiplier that's needed to fit the image to
   // the window, taking into account page zoom and device scale.
   float scale() const;
 
   Member<HTMLDivElement> m_divElement;
   Member<HTMLImageElement> m_imageElement;
 
   // Whether enough of the image has been loaded to determine its size
   bool m_imageSizeIsKnown;
 
   // Whether the image is shrunk to fit or not
   bool m_didShrinkImage;
 
   // Whether the image should be shrunk or not
   bool m_shouldShrinkImage;
 
+  // Whether the image has finished loading or not
+  bool m_imageIsLoaded;
+
+  // Size of the checkerboard background tiles
+  int m_checkerSize;
+
   enum ShrinkToFitMode { Viewport, Desktop };
   ShrinkToFitMode m_shrinkToFitMode;
 };
 
 DEFINE_DOCUMENT_TYPE_CASTS(ImageDocument);
 
 }  // namespace blink
 
 #endif  // ImageDocument_h