replace arcto quads with a conic

src/core/SkGeometry.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkGeometry_DEFINED
 #define SkGeometry_DEFINED
 
@@ skipping 176 matching lines @@
 */
 SkCubicType SkClassifyCubic(const SkPoint p[4], SkScalar inflection[3]);
 
 ///////////////////////////////////////////////////////////////////////////////
 
 enum SkRotationDirection {
     kCW_SkRotationDirection,
     kCCW_SkRotationDirection
 };
 
+#ifdef SK_SUPPORT_LEGACY_ARCTO
 /** Maximum number of points needed in the quadPoints[] parameter for
     SkBuildQuadArc()
 */
 #define kSkBuildQuadArcStorage  17
 
 /** Given 2 unit vectors and a rotation direction, fill out the specified
     array of points with quadratic segments. Return is the number of points
     written to, which will be { 0, 3, 5, 7, ... kSkBuildQuadArcStorage }
 
     matrix, if not null, is appled to the points before they are returned.
 */
 int SkBuildQuadArc(const SkVector& unitStart, const SkVector& unitStop,
                    SkRotationDirection, const SkMatrix*, SkPoint quadPoints[]);
+#endif
 
 struct SkConic {
     SkConic() {}
     SkConic(const SkPoint& p0, const SkPoint& p1, const SkPoint& p2, SkScalar w) {
         fPts[0] = p0;
         fPts[1] = p1;
         fPts[2] = p2;
         fW = w;
     }
     SkConic(const SkPoint pts[3], SkScalar w) {
@@ skipping 209 matching lines @@
 private:
     enum {
         kQuadCount = 8, // should handle most conics
         kPointCount = 1 + 2 * kQuadCount,
     };
     SkAutoSTMalloc<kPointCount, SkPoint> fStorage;
     int fQuadCount; // #quads for current usage
 };
 
 #endif