DM: add a pixel check to serialize

dm/DMSrcSink.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "DMSrcSink.h"
 #include "SamplePipeControllers.h"
 #include "SkAndroidCodec.h"
@@ skipping 1066 matching lines @@
                                                         : nullptr);
         SkAutoTDelete<SkCanvas> canvas(SkRemote::NewCanvas(cache ? cache : decoder));
         return src.draw(canvas);
     });
 }
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 Error ViaSerialization::draw(
         const Src& src, SkBitmap* bitmap, SkWStream* stream, SkString* log) const {
+    // Draw the Src directly as a reference.
+    SkBitmap reference;
+    if (bitmap) {
+        Error err = fSink->draw(src, &reference, nullptr, log);
+        if (!err.isEmpty()) {
+            return err;
+        }
+    }
+
     // Record our Src into a picture.
     auto size = src.size();
     SkPictureRecorder recorder;
     Error err = src.draw(recorder.beginRecording(SkIntToScalar(size.width()),
                                                  SkIntToScalar(size.height())));
     if (!err.isEmpty()) {
         return err;
     }
     SkAutoTUnref<SkPicture> pic(recorder.endRecording());
 
     // Serialize it and then deserialize it.
     SkDynamicMemoryWStream wStream;
     pic->serialize(&wStream);
     SkAutoTDelete<SkStream> rStream(wStream.detachAsStream());
     SkAutoTUnref<SkPicture> deserialized(SkPicture::CreateFromStream(rStream, &lazy_decode_bitmap));
 
     return draw_to_canvas(fSink, bitmap, stream, log, size, [&](SkCanvas* canvas) {
         canvas->drawPicture(deserialized);
+        // Check against the reference if we have one.
+        if (bitmap) {
+            if (reference.getSize() != bitmap->getSize()) {
+                return "Serialized and direct have different dimensions.";
+            }
+            if (0 != memcmp(reference.getPixels(), bitmap->getPixels(), reference.getSize())) {
+                return "Serialized and direct have different pixels.";
+            }
+        }
         return "";
     });
 }
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 ViaTiles::ViaTiles(int w, int h, SkBBHFactory* factory, Sink* sink)
     : Via(sink)
     , fW(w)
     , fH(h)
@@ skipping 149 matching lines @@
             skr.visit<void>(i, drawsAsSingletonPictures);
         }
         SkAutoTUnref<SkPicture> macroPic(macroRec.endRecordingAsPicture());
 
         canvas->drawPicture(macroPic);
         return "";
     });
 }
 
 }  // namespace DM