Remove Cairo support.

Source/WebCore/platform/graphics/Gradient.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2008 Torch Mobile, Inc.
  *
  * 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.
@@ skipping 29 matching lines @@
 typedef struct CGContext* CGContextRef;
 
 typedef struct CGGradient* CGGradientRef;
 typedef CGGradientRef PlatformGradient;
 
 #elif PLATFORM(QT)
 QT_BEGIN_NAMESPACE
 class QGradient;
 QT_END_NAMESPACE
 typedef QGradient* PlatformGradient;
-#elif USE(CAIRO)
-typedef struct _cairo_pattern cairo_pattern_t;
-typedef cairo_pattern_t* PlatformGradient;
 #elif USE(SKIA)
 class SkShader;
 typedef class SkShader* PlatformGradient;
 typedef class SkShader* PlatformPattern;
 #elif PLATFORM(WX)
 class wxGraphicsBrush;
 typedef wxGraphicsBrush* PlatformGradient;
 #else
 typedef void* PlatformGradient;
 #endif
@@ skipping 101 matching lines @@
         virtual void adjustParametersForTiledDrawing(IntSize& size, FloatRect& srcRect);
 
         void setPlatformGradientSpaceTransform(const AffineTransform& gradientSpaceTransformation);
 
         virtual unsigned hash() const OVERRIDE;
         void invalidateHash() { m_cachedHash = 0; }
 
 #if USE(CG)
         void paint(CGContextRef);
         void paint(GraphicsContext*);
-#elif USE(CAIRO)
-        PlatformGradient platformGradient(float globalAlpha);
 #endif
 
     private:
         Gradient(const FloatPoint& p0, const FloatPoint& p1);
         Gradient(const FloatPoint& p0, float r0, const FloatPoint& p1, float r1, float aspectRatio);
 
         void platformInit() { m_gradient = 0; }
         void platformDestroy();
 
         int findStop(float value) const;
         void sortStopsIfNecessary();
 
         // Keep any parameters relevant to rendering in sync with the structure in Gradient::hash().
         bool m_radial;
         FloatPoint m_p0;
         FloatPoint m_p1;
         float m_r0;
         float m_r1;
         float m_aspectRatio; // For elliptical gradient, width / height.
         mutable Vector<ColorStop, 2> m_stops;
         mutable bool m_stopsSorted;
         mutable int m_lastStop;
         GradientSpreadMethod m_spreadMethod;
         AffineTransform m_gradientSpaceTransformation;
 
         mutable unsigned m_cachedHash;
 
         PlatformGradient m_gradient;
-
-#if USE(CAIRO)
-        float m_platformGradientAlpha;
-#endif
-
     };
 
 } //namespace
 
 #endif