Don't create a GXPFactory when blend is SrcOver

gm/convexpolyeffect.cpp

 
 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 // This test only works with the GPU backend.
 
@@ skipping 172 matching lines @@
                 SkPath p;
                 path->transform(m, &p);
 
                 GrPrimitiveEdgeType edgeType = (GrPrimitiveEdgeType) et;
                 SkAutoTUnref<GrFragmentProcessor> fp(GrConvexPolyEffect::Create(edgeType, p));
                 if (!fp) {
                     continue;
                 }
 
                 GrPipelineBuilder pipelineBuilder;
+                pipelineBuilder.setXPFactory(
+                    GrPorterDuffXPFactory::Create(SkXfermode::kSrc_Mode))->unref();
                 pipelineBuilder.addCoverageFragmentProcessor(fp);
                 pipelineBuilder.setRenderTarget(rt);
 
                 ConvexPolyTestBatch::Geometry geometry;
                 geometry.fColor = color.fColor;
                 geometry.fBounds = p.getBounds();
 
                 SkAutoTUnref<GrDrawBatch> batch(ConvexPolyTestBatch::Create(gp, geometry));
 
                 tt.target()->drawBatch(pipelineBuilder, batch);
@@ skipping 29 matching lines @@
                 }
                 SkRect rect = *iter.get();
                 rect.offset(x, y);
                 GrPrimitiveEdgeType edgeType = (GrPrimitiveEdgeType) et;
                 SkAutoTUnref<GrFragmentProcessor> fp(GrConvexPolyEffect::Create(edgeType, rect));
                 if (!fp) {
                     continue;
                 }
 
                 GrPipelineBuilder pipelineBuilder;
+                pipelineBuilder.setXPFactory(
+                    GrPorterDuffXPFactory::Create(SkXfermode::kSrc_Mode))->unref();
                 pipelineBuilder.addCoverageFragmentProcessor(fp);
                 pipelineBuilder.setRenderTarget(rt);
 
                 ConvexPolyTestBatch::Geometry geometry;
                 geometry.fColor = color.fColor;
                 geometry.fBounds = rect;
 
                 SkAutoTUnref<GrDrawBatch> batch(ConvexPolyTestBatch::Create(gp, geometry));
 
                 tt.target()->drawBatch(pipelineBuilder, batch);
@@ skipping 21 matching lines @@
     PathList fPaths;
     RectList fRects;
 
     typedef GM INHERITED;
 };
 
 DEF_GM(return new ConvexPolyEffect;)
 }
 
 #endif