change old picture serialization to really handle images

src/core/SkBitmap.cpp

Index: src/core/SkBitmap.cpp
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index 49e2c04bfb9a20215e39538e231ec043e0595351..e72533aa588d082b39081c8152ac3e904e682a5a 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -1270,7 +1270,7 @@ bool SkBitmap::requestLock(SkAutoPixmapUnlock* result) const {
         return false;
     }
 
-    SkPixelRef::LockRequest req = { fInfo.dimensions(), kNone_SkFilterQuality };
+    SkPixelRef::LockRequest req = { pr->info().dimensions(), kNone_SkFilterQuality };

[scroggo, 2015/06/22 17:40:01]

Why this change?

[reed1, 2015/06/22 18:41:50]

I'll add a comment -- the pixelref cannot do subset-locks (nor does the API
allow the offset to be specified). The older code was a bug waiting to happen if
in fact the bitmap *is* a subset of the pixelref.

     SkPixelRef::LockResult res;
     if (pr->requestLock(req, &res)) {
         SkASSERT(res.fPixels);