avoid generating degenerate conic from arc

gm/circulararcs.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include <functional>
 #include "SkCanvas.h"
 #include "SkDashPathEffect.h"
@@ skipping 192 matching lines @@
             canvas->translate(kS + kPad, 0.f);
         }
         for (auto arc : arcs) {
             canvas->drawArc(arc.fOval, arc.fStart, arc.fSweep, true, paint);
             canvas->translate(kS + kPad, 0.f);
         }
         canvas->restore();
         canvas->translate(0, kS + kPad);
     }
 }
+
+DEF_SIMPLE_GM(onebadarc, canvas, 100, 100) {
+    SkPath path;
+    path.moveTo(SkBits2Float(0x41a00000), SkBits2Float(0x41a00000));  // 20, 20
+    path.lineTo(SkBits2Float(0x4208918c), SkBits2Float(0x4208918c));  // 34.1421f, 34.1421f
+    path.conicTo(SkBits2Float(0x41a00000), SkBits2Float(0x42412318),  // 20, 48.2843f
+            SkBits2Float(0x40bb73a0), SkBits2Float(0x4208918c),       // 5.85786f, 34.1421f
+            SkBits2Float(0x3f3504f3));                                // 0.707107f
+    path.quadTo(SkBits2Float(0x40bb73a0), SkBits2Float(0x4208918c),   // 5.85786f, 34.1421f
+            SkBits2Float(0x40bb73a2), SkBits2Float(0x4208918c));      // 5.85787f, 34.1421f
+    path.lineTo(SkBits2Float(0x41a00000), SkBits2Float(0x41a00000));  // 20, 20
+    path.close();
+    SkPaint p0;
+    p0.setColor(SK_ColorRED);
+    p0.setStrokeWidth(15.f);
+    p0.setStyle(SkPaint::kStroke_Style);
+    p0.setAlpha(100);
+    canvas->translate(20, 0);
+    canvas->drawPath(path, p0);
+
+    SkRect kRect = { 60, 0, 100, 40};
+    canvas->drawArc(kRect, 45, 90, true, p0);
+}