Make lines a special case in GrShape

src/gpu/batches/GrDashLinePathRenderer.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDashLinePathRenderer.h"
 
 #include "GrGpu.h"
 #include "GrAuditTrail.h"
 #include "effects/GrDashingEffect.h"
 
 bool GrDashLinePathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
     SkPoint pts[2];
-    if (args.fShape->style().isDashed() && args.fShape->asLine(pts)) {
+    bool inverted;
+    if (args.fShape->style().isDashed() && args.fShape->asLine(pts, &inverted)) {
+        // We should never have an inverse dashed case.
+        SkASSERT(!inverted);
         return GrDashingEffect::CanDrawDashLine(pts, args.fShape->style(), *args.fViewMatrix);
     }
     return false;
 }
 
 bool GrDashLinePathRenderer::onDrawPath(const DrawPathArgs& args) {
     GR_AUDIT_TRAIL_AUTO_FRAME(args.fDrawContext->auditTrail(),
                               "GrDashLinePathRenderer::onDrawPath");
     bool useHWAA = args.fDrawContext->isUnifiedMultisampled();
     GrDashingEffect::AAMode aaMode;
     if (useHWAA) {
         // We ignore args.fAntiAlias here and force anti aliasing when using MSAA. Otherwise,
         // we can wind up with external edges antialiased and internal edges unantialiased.
         aaMode = GrDashingEffect::AAMode::kCoverageWithMSAA;
     } else if (args.fAntiAlias) {
         aaMode = GrDashingEffect::AAMode::kCoverage;
     } else {
         aaMode = GrDashingEffect::AAMode::kNone;
     }
     SkPoint pts[2];
-    SkAssertResult(args.fShape->asLine(pts));
+    SkAssertResult(args.fShape->asLine(pts, nullptr));
     SkAutoTUnref<GrDrawBatch> batch(GrDashingEffect::CreateDashLineBatch(args.fColor,
                                                                          *args.fViewMatrix,
                                                                          pts,
                                                                          aaMode,
                                                                          args.fShape->style()));
     if (!batch) {
         return false;
     }
 
     GrPipelineBuilder pipelineBuilder(*args.fPaint, useHWAA);
     pipelineBuilder.setUserStencil(args.fUserStencilSettings);
 
     args.fDrawContext->drawBatch(pipelineBuilder, *args.fClip, batch);
     return true;
 }