Add control over whether lines are special cased in SkDashPath. Disable when called from GrShape.

src/gpu/GrShape.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrShape_DEFINED
 #define GrShape_DEFINED
 
@@ skipping 150 matching lines @@
         }
         if (start) {
             *start = fRRectStart;
         }
         if (inverted) {
             *inverted = fRRectIsInverted;
         }
         return true;
     }
 
+    /**
+     * If the unstyled shape is a straight line segment, returns true and sets pts to the endpoints.
+     * An inverse filled line path is still considered a line.
+     */
+     bool asLine(SkPoint pts[2]) const {
+         if (fType != Type::kPath) {
+             return false;
+         }
+         return fPath.get()->isLine(pts);
+     }
+
     /** Returns the unstyled geometry as a path. */
     void asPath(SkPath* out) const {
         switch (fType) {
             case Type::kEmpty:
                 out->reset();
                 break;
             case Type::kRRect:
                 out->reset();
                 out->addRRect(fRRect, fRRectDir, fRRectStart);
                 if (fRRectIsInverted) {
@@ skipping 167 matching lines @@
     Type                        fType;
     SkRRect                     fRRect;
     SkPath::Direction           fRRectDir;
     unsigned                    fRRectStart;
     bool                        fRRectIsInverted;
     SkTLazy<SkPath>             fPath;
     GrStyle                     fStyle;
     SkAutoSTArray<8, uint32_t>  fInheritedKey;
 };
 #endif