SkBitmapRegionCodec needs to use the rowBytes on the pixel ref

tools/SkBitmapRegionCodec.cpp

Index: tools/SkBitmapRegionCodec.cpp
diff --git a/tools/SkBitmapRegionCodec.cpp b/tools/SkBitmapRegionCodec.cpp
index cac99452e0d37bcffdf762063bf9e17c7c0515c5..0af7b62473e4eb4cda4a30fc1dd7bc2a58c78686 100644
--- a/tools/SkBitmapRegionCodec.cpp
+++ b/tools/SkBitmapRegionCodec.cpp
@@ -9,6 +9,7 @@
 #include "SkAndroidCodec.h"
 #include "SkCodecPriv.h"
 #include "SkCodecTools.h"
+#include "SkPixelRef.h"
 
 SkBitmapRegionCodec::SkBitmapRegionCodec(SkAndroidCodec* codec)
     : INHERITED(codec->getInfo().width(), codec->getInfo().height())
@@ -93,7 +94,7 @@ bool SkBitmapRegionCodec::decodeRegion(SkBitmap* bitmap, SkBitmap::Allocator* al
         scaledOutHeight += scaledOutY + scaledExtraY;
     }
     SkImageInfo outInfo = decodeInfo.makeWH(scaledOutWidth, scaledOutHeight);
-    bitmap->setInfo(outInfo, outInfo.minRowBytes());
+    bitmap->setInfo(outInfo);
     if (!bitmap->tryAllocPixels(allocator, colorTable.get())) {
         SkCodecPrintf("Error: Could not allocate pixels.\n");
         return false;
@@ -119,7 +120,14 @@ bool SkBitmapRegionCodec::decodeRegion(SkBitmap* bitmap, SkBitmap::Allocator* al
     options.fColorPtr = colorPtr;
     options.fColorCount = colorCountPtr;
     void* dst = bitmap->getAddr(scaledOutX, scaledOutY);
-    size_t rowBytes = bitmap->rowBytes();
+
+    // FIXME: skbug.com/4538
+    // It is important that we use the rowBytes on the pixelRef.  They may not be
+    // set properly on the bitmap.
+    SkPixelRef* pr = SkRef(bitmap->pixelRef());

[scroggo, 2015/11/05 22:45:56]

I just want to double check that the ref counting is correct here...

Say pixelRef has a refCount of RC. After this call, it is RC + 1

+    size_t rowBytes = pr->rowBytes();
+    bitmap->setInfo(outInfo, rowBytes);

[scroggo, 2015/11/05 22:45:56]

Behind our backs, this decrements the refCount, so it is back to RC

+    bitmap->setPixelRef(pr)->unref();

[scroggo, 2015/11/05 22:45:56]

setPixelRef increments it again (RC + 1) and then we immediately unref it (RC).

lgtm

[msarett, 2015/11/05 22:49:05]

Looks correct to me as well.

     SkCodec::Result result = fCodec->getAndroidPixels(decodeInfo, dst, rowBytes, &options);
     if (SkCodec::kSuccess != result && SkCodec::kIncompleteInput != result) {
         SkCodecPrintf("Error: Could not get pixels.\n");