Revert of SkTreatAsSprite should take AA into account (patchset #5 id:80001 of https://codereview.chromium.org/1566943002/ )

Reason for revert:
Need to use SkLeftShift since the arg could be negative

Original issue's description:
> SkTreatAsSprite should take AA into account
>
> Currently we always call SkTreatAsSprite with 0 subpixel bits, which means
> subpixel translations are ignored.  This is incorrect for the anti-aliased
> case (drawSprite always pixel-snaps, so we lose edge AA).
>
> The CL updates SkTreatAsSprite to take an SkPaint argument and use 8 subpixel
> bits when AA is requested.
>
> Also remove unused SkTreatAsSpriteFilter.
>
> BUG=skia:4761
> R=reed@google.com
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1566943002
>
> Committed: https://skia.googlesource.com/skia/+/983dc2541a729609037a05eba731b3eb9788c517

TBR=fmalita@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:4761

Review URL: https://codereview.chromium.org/1569873003

1 files changed, 23 insertions, 6 deletions

diff --git a/src/core/SkMatrixUtils.h b/src/core/SkMatrixUtils.h
index 0e01fbe953..d1b6658d07 100644
--- a/src/core/SkMatrixUtils.h
+++ b/src/core/SkMatrixUtils.h
@@ -8,20 +8,37 @@
 #ifndef SkMatrixUtils_DEFINED
 #define SkMatrixUtils_DEFINED
 
-#include "SkSize.h"
+#include "SkMatrix.h"
 
-class SkMatrix;
-class SkPaint;
+/**
+ *  Number of subpixel bits used in skia's bilerp.
+ *  See SkBitmapProcState_procs.h and SkBitmapProcState_filter.h
+ */
+#define kSkSubPixelBitsForBilerp   4
 
 /**
- *  Given a matrix, size and paint, return true if the computed dst-rect would
+ *  Given a matrix and width/height, return true if the computed dst-rect would
  *  align such that there is a 1-to-1 coorspondence between src and dst pixels.
  *  This can be called by drawing code to see if drawBitmap can be turned into
  *  drawSprite (which is faster).
  *
- *  The src-rect is defined to be { 0, 0, size.width(), size.height() }
+ *  The src-rect is defined to be { 0, 0, width, height }
+ *
+ *  The "closeness" test is based on the subpixelBits parameter. Pass 0 for
+ *  round-to-nearest behavior (e.g. nearest neighbor sampling). Pass the number
+ *  of subpixel-bits to simulate filtering.
+ */
+bool SkTreatAsSprite(const SkMatrix&, int width, int height,
+                     unsigned subpixelBits);
+
+/**
+ *  Calls SkTreatAsSprite() with default subpixelBits value to match Skia's
+ *  filter-bitmap implementation (i.e. kSkSubPixelBitsForBilerp).
  */
-bool SkTreatAsSprite(const SkMatrix&, const SkISize& size, const SkPaint& paint);
+static inline bool SkTreatAsSpriteFilter(const SkMatrix& matrix,
+                                         int width, int height) {
+    return SkTreatAsSprite(matrix, width, height, kSkSubPixelBitsForBilerp);
+}
 
 /** Decomposes the upper-left 2x2 of the matrix into a rotation (represented by
     the cosine and sine of the rotation angle), followed by a non-uniform scale,