Set analytic AA as default.

src/core/SkPath.cpp

 /*
  * 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.
  */
 
 #include <cmath>
 #include "SkBuffer.h"
 #include "SkCubicClipper.h"
@@ skipping 1724 matching lines @@
         dst->fFirstDirection = SkPathPriv::kUnknown_FirstDirection;
     } else {
         SkPathRef::CreateTransformedCopy(&dst->fPathRef, *fPathRef.get(), matrix);
 
         if (this != dst) {
             dst->fFillType = fFillType;
             dst->fConvexity = fConvexity;
             dst->fIsVolatile = fIsVolatile;
         }
 
+        dst->fConvexity = SkPath::kUnknown_Convexity;

[reed1, 2016/11/07 15:31:42]

If we're going to leave this in for real, please add a comment and a bug as to
why. This has performance implications so we shouldn't leave this here
unnecessarily.

[liyuqian, 2016/11/07 16:08:00]

Done.

+
         if (SkPathPriv::kUnknown_FirstDirection == fFirstDirection) {
             dst->fFirstDirection = SkPathPriv::kUnknown_FirstDirection;
         } else {
             SkScalar det2x2 =
                 SkScalarMul(matrix.get(SkMatrix::kMScaleX), matrix.get(SkMatrix::kMScaleY)) -
                 SkScalarMul(matrix.get(SkMatrix::kMSkewX), matrix.get(SkMatrix::kMSkewY));
             if (det2x2 < 0) {
                 dst->fFirstDirection = SkPathPriv::OppositeFirstDirection(
                         (SkPathPriv::FirstDirection)fFirstDirection.load());
             } else if (det2x2 > 0) {
@@ skipping 1636 matching lines @@
         path->arcTo(oval, startAngle, 180.f, false);
         startAngle += 180.f;
         forceMoveTo = false;
         sweepAngle -= 360.f;
     }
     path->arcTo(oval, startAngle, sweepAngle, forceMoveTo);
     if (useCenter) {
         path->close();
     }
 }