fix trivial matrix computation

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"
 
@@ skipping 1170 matching lines @@
                                 kVertsPerQuad*n,                   // vCount
                                 kIdxsPerQuad*n,                    // iCount
                                 &devBounds);
             conics += n;
         }
     }
     target->resetIndexSource();
 
     return true;
 }
-