Add drawBitmapLattice() API

src/core/SkNinePatchIter.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkNinePatchIter_DEFINED
 #define SkNinePatchIter_DEFINED
 
+#include "SkCanvas.h"
 #include "SkScalar.h"
+#include "SkTArray.h"
 
 struct SkIRect;
 struct SkRect;
 
 /**
  *  Disect a ninepatch request into an sequence of src-rect / dst-rect pairs
  */
 class SkNinePatchIter {
 public:
+
+    static bool Valid(int imageWidth, int imageHeight, const SkCanvas::NinePatchDivs& divs);
+
+    SkNinePatchIter(int imageWidth, int imageHeight, const SkCanvas::NinePatchDivs& divs,
+                    const SkRect& dst);
+
     static bool Valid(int imageWidth, int imageHeight, const SkIRect& center);
 
     SkNinePatchIter(int imageWidth, int imageHeight, const SkIRect& center, const SkRect& dst);
 
     /**
      *  While it returns true, use src/dst to draw the image/bitmap
      */
     bool next(SkRect* src, SkRect* dst);
 
 private:
-    SkScalar fSrcX[4];
-    SkScalar fSrcY[4];
-    SkScalar fDstX[4];
-    SkScalar fDstY[4];
+    SkTArray<SkScalar> fSrcX;
+    SkTArray<SkScalar> fSrcY;
+    SkTArray<SkScalar> fDstX;
+    SkTArray<SkScalar> fDstY;
 
     int fCurrX;
     int fCurrY;
     bool fDone;
 };
 
 #endif