fix for ASAN heap overflow

src/gpu/GrAAHairLinePathRenderer.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrAAHairLinePathRenderer.h"
 
 #include "GrBatch.h"
@@ skipping 851 matching lines @@
                                   batchTarget->caps(),
                                   *geometryProcessorLocalM,
                                   this->coverage()));
 
     // This is hand inlined for maximum performance.
     PREALLOC_PTARRAY(128) lines;
     PREALLOC_PTARRAY(128) quads;
     PREALLOC_PTARRAY(128) conics;
     IntArray qSubdivs;
     FloatArray cWeights;
+    int quadCount = 0;
 
     int instanceCount = fGeoData.count();
     for (int i = 0; i < instanceCount; i++) {
         const Geometry& args = fGeoData[i];
-        gather_lines_and_quads(args.fPath, args.fViewMatrix, args.fDevClipBounds,
-                               &lines, &quads, &conics, &qSubdivs, &cWeights);
+        quadCount += gather_lines_and_quads(args.fPath, args.fViewMatrix, args.fDevClipBounds,
+                                            &lines, &quads, &conics, &qSubdivs, &cWeights);
     }
 
-    int quadCount = quads.count() / 3;
     int lineCount = lines.count() / 2;
     int conicCount = conics.count() / 3;
 
     // do lines first
     if (lineCount) {
         batchTarget->initDraw(lineGP, pipeline);
 
         // TODO remove this when batch is everywhere
         GrPipelineInfo init;
         init.fColorIgnored = fBatch.fColorIgnored;
@@ skipping 47 matching lines @@
         size_t vertexStride = sizeof(BezierVertex);
         int vertexCount = kQuadNumVertices * quadCount + kQuadNumVertices * conicCount;
         void *vertices = batchTarget->vertexPool()->makeSpace(vertexStride,
                                                               vertexCount,
                                                               &vertexBuffer,
                                                               &firstVertex);
 
         // Setup vertices
         BezierVertex* verts = reinterpret_cast<BezierVertex*>(vertices);
 
-        // is this the same as quadcount? TODO
         int unsubdivQuadCnt = quads.count() / 3;
         for (int i = 0; i < unsubdivQuadCnt; ++i) {
             SkASSERT(qSubdivs[i] >= 0);
             add_quads(&quads[3*i], qSubdivs[i], toDevice, toSrc, &verts);
         }
 
         // Start Conics
         for (int i = 0; i < conicCount; ++i) {
             add_conics(&conics[3*i], cWeights[i], toDevice, toSrc, &verts);
         }
@@ skipping 93 matching lines @@
     geometry.fPath = path;
     SkDEBUGCODE(geometry.fDevBounds = devRect;)
     geometry.fDevClipBounds = devClipBounds;
 
     SkAutoTUnref<GrBatch> batch(AAHairlineBatch::Create(geometry, fLinesIndexBuffer,
                                                         fQuadsIndexBuffer));
     target->drawBatch(pipelineBuilder, batch, &devRect);
 
     return true;
 }