Refactor SkBitmapRegionDecoderInterface for Android

dm/DMSrcSink.cpp

Index: dm/DMSrcSink.cpp
diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index e0ec5e139ce988d07a8dbfe76a34b0ba2611a279..5eff189fa81b649c06269c223b292c88f93df14c 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -125,12 +125,16 @@ Error BRDSrc::draw(SkCanvas* canvas) const {
     }
     switch (fMode) {
         case kFullImage_Mode: {
-            SkAutoTDelete<SkBitmap> bitmap(brd->decodeRegion(0, 0, width, height, fSampleSize,
-                    colorType));
-            if (nullptr == bitmap.get() || colorType != bitmap->colorType()) {
+            SkBitmap bitmap;
+            if (!brd->decodeRegion(&bitmap, nullptr, SkIRect::MakeXYWH(0, 0, width, height),
+                    fSampleSize, colorType, false)) {
+                // FIXME: Make this a fatal error.

[scroggo, 2015/10/27 18:53:55]

Why is this not fatal, and what do you need to do to make it a fatal error?
(Same below)

[msarett, 2015/10/27 19:06:16]

I *think* the only thing that needs to be done is to disable webps for
Canvas_Strategy.  Canvas_Strategy uses a scanline decoder.

I was going to make it fatal in this CL, but I realized that it would require an
additional change and didn't want to add too much in one go.

A bad color conversion in kOriginal_Strategy may also fail here.  I know that
some of the time, they will just decode to a default colorType, but I'm not sure
if it's all of the time.

[scroggo, 2015/10/27 19:23:37]

I'm fine if that is left to a separate change, but can you update the comment
with more details and file a bug?

+                return Error::Nonfatal("Cannot decode region.\n");
+            }
+            if (colorType != bitmap.colorType()) {
                 return Error::Nonfatal("Cannot convert to color type.\n");
             }
-            canvas->drawBitmap(*bitmap, 0, 0);
+            canvas->drawBitmap(bitmap, 0, 0);
             return "";
         }
         case kDivisor_Mode: {
@@ -178,13 +182,17 @@ Error BRDSrc::draw(SkCanvas* canvas) const {
                     const int decodeTop = top - unscaledBorder;
                     const uint32_t decodeWidth = subsetWidth + unscaledBorder * 2;
                     const uint32_t decodeHeight = subsetHeight + unscaledBorder * 2;
-                    SkAutoTDelete<SkBitmap> bitmap(brd->decodeRegion(decodeLeft,
-                            decodeTop, decodeWidth, decodeHeight, fSampleSize, colorType));
-                    if (nullptr == bitmap.get() || colorType != bitmap->colorType()) {
+                    SkBitmap bitmap;
+                    if (!brd->decodeRegion(&bitmap, nullptr, SkIRect::MakeXYWH(decodeLeft,
+                            decodeTop, decodeWidth, decodeHeight), fSampleSize, colorType, false)) {
+                        // FIXME: Make this a fatal error.
+                        return Error::Nonfatal("Cannot not decode region.\n");
+                    }
+                    if (colorType != bitmap.colorType()) {
                         return Error::Nonfatal("Cannot convert to color type.\n");
                     }
 
-                    canvas->drawBitmapRect(*bitmap,
+                    canvas->drawBitmapRect(bitmap,
                             SkRect::MakeXYWH((SkScalar) scaledBorder, (SkScalar) scaledBorder,
                                     (SkScalar) (subsetWidth / fSampleSize),
                                     (SkScalar) (subsetHeight / fSampleSize)),