Batched implementation of drawLattice() for GPU

src/core/SkLatticeIter.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 "SkLatticeIter.h"
 #include "SkRect.h"
 
@@ skipping 210 matching lines @@
     dst->set(fDstX[x], fDstY[y], fDstX[x + 1], fDstY[y + 1]);
     if (fSrcX.count() - 1 == ++fCurrX) {
         fCurrX = 0;
         fCurrY += 1;
         if (fCurrY >= fSrcY.count() - 1) {
             fDone = true;
         }
     }
     return true;
 }
+
+int SkLatticeIter::numRects() const {
+    SkASSERT(fSrcX.count() == fDstX.count() && fSrcY.count() == fDstY.count());
+    SkASSERT(fSrcX.count() >= 2 && fDstX.count() >= 2);
+    return (fSrcX.count() - 1) * (fDstX.count() - 1);
+}