pass dst-rect through from drawBitmapRect for better precision

src/core/SkBitmapDevice.cpp

Index: src/core/SkBitmapDevice.cpp
diff --git a/src/core/SkBitmapDevice.cpp b/src/core/SkBitmapDevice.cpp
index 020f1da13b2faba3910d303479e5b5d0d9754c5f..1f17e6fac12d30212f62819c75cd6fa47b6986ea 100644
--- a/src/core/SkBitmapDevice.cpp
+++ b/src/core/SkBitmapDevice.cpp
@@ -218,7 +218,7 @@ void SkBitmapDevice::drawPath(const SkDraw& draw, const SkPath& path,
 
 void SkBitmapDevice::drawBitmap(const SkDraw& draw, const SkBitmap& bitmap,
                                 const SkMatrix& matrix, const SkPaint& paint) {
-    draw.drawBitmap(bitmap, matrix, paint);
+    draw.drawBitmap(bitmap, matrix, NULL, paint);
 }
 
 void SkBitmapDevice::drawBitmapRect(const SkDraw& draw, const SkBitmap& bitmap,
@@ -291,7 +291,7 @@ void SkBitmapDevice::drawBitmapRect(const SkDraw& draw, const SkBitmap& bitmap,
         // We can go faster by just calling drawBitmap, which will concat the
         // matrix with the CTM, and try to call drawSprite if it can. If not,
         // it will make a shader and call drawRect, as we do below.
-        this->drawBitmap(draw, *bitmapPtr, matrix, paint);
+        draw.drawBitmap(*bitmapPtr, matrix, dstPtr, paint);
         return;
     }