Remove GraphicsContext::strokeArc, which is unused.

Source/core/platform/graphics/GraphicsContext.h

 /*
  * Copyright (C) 2003, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2008-2009 Torch Mobile, Inc.
  * 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 207 matching lines @@
         void drawLine(const IntPoint&, const IntPoint&);
         void drawEllipse(const IntRect&);
         void drawConvexPolygon(size_t numPoints, const FloatPoint*, bool shouldAntialias = false);
 
         void fillPath(const Path&);
         void strokePath(const Path&);
 
         void fillEllipse(const FloatRect&);
         void strokeEllipse(const FloatRect&);
 
-        // Arc drawing (used by border-radius in CSS) just supports stroking at the moment.
-        void strokeArc(const IntRect&, int startAngle, int angleSpan);
-
         void fillRect(const FloatRect&);
         void fillRect(const FloatRect&, const Color&, ColorSpace);
         void fillRect(const FloatRect&, Generator&);
         void fillRect(const FloatRect&, const Color&, ColorSpace, CompositeOperator);
         void fillRoundedRect(const IntRect&, const IntSize& topLeft, const IntSize& topRight, const IntSize& bottomLeft, const IntSize& bottomRight, const Color&, ColorSpace);
         void fillRoundedRect(const RoundedRect&, const Color&, ColorSpace);
         void fillRectWithRoundedHole(const IntRect&, const RoundedRect& roundedHoleRect, const Color&, ColorSpace);
 
         void clearRect(const FloatRect&);
 
@@ skipping 197 matching lines @@
 
     private:
         GraphicsContext& m_context;
         bool m_saveAndRestore;
     };
 
 } // namespace WebCore
 
 #endif // GraphicsContext_h