When filling nested rect path check for empty inner and empty outer rects

src/gpu/GrDrawContext.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 "GrBatchTest.h"
 #include "GrColor.h"
 #include "GrDrawContext.h"
@@ skipping 804 matching lines @@
     AutoCheckFlush acf(fDrawingManager);
 
     if (should_apply_coverage_aa(paint, fRenderTarget.get()) && !strokeInfo.isDashed()) {
         if (strokeInfo.getWidth() < 0 && !path.isConvex()) {
             // Concave AA paths are expensive - try to avoid them for special cases
             SkRect rects[2];
 
             if (is_nested_rects(viewMatrix, path, strokeInfo, rects)) {
                 SkAutoTUnref<GrDrawBatch> batch(GrRectBatchFactory::CreateAAFillNestedRects(
                     paint.getColor(), viewMatrix, rects));
-
-                GrPipelineBuilder pipelineBuilder(paint, fRenderTarget.get(), clip);
-                this->getDrawTarget()->drawBatch(pipelineBuilder, batch);
+                if (batch) {
+                    GrPipelineBuilder pipelineBuilder(paint, fRenderTarget.get(), clip);
+                    this->getDrawTarget()->drawBatch(pipelineBuilder, batch);
+                }
                 return;
             }
         }
         SkRect ovalRect;
         bool isOval = path.isOval(&ovalRect);
 
         if (isOval && !path.isInverseFillType()) {
             GrShaderCaps* shaderCaps = fContext->caps()->shaderCaps();
             SkAutoTUnref<GrDrawBatch> batch(GrOvalRenderer::CreateOvalBatch(paint.getColor(),
                                                                             viewMatrix,
@@ skipping 195 matching lines @@
 }
 
 void GrDrawContext::drawBatch(GrPipelineBuilder* pipelineBuilder, GrDrawBatch* batch) {
     ASSERT_SINGLE_OWNER
     RETURN_IF_ABANDONED
     SkDEBUGCODE(this->validate();)
     GR_AUDIT_TRAIL_AUTO_FRAME(fAuditTrail, "GrDrawContext::drawBatch");
 
     this->getDrawTarget()->drawBatch(*pipelineBuilder, batch);
 }