DM: duh, don't calculate digests unless we're going to look at them.

dm/DMReplayTask.cpp

 #include "DMReplayTask.h"
 #include "DMUtil.h"
 
 #include "SkPicture.h"
 
 namespace DM {
 
 ReplayTask::ReplayTask(const char* suffix,
                        const Task& parent,
                        skiagm::GM* gm,
-                       skiagm::GmResultDigest reference,
-                       SkBitmap::Config config)
+                       SkBitmap reference)
     : Task(parent)
     , fName(underJoin(parent.name().c_str(), suffix))
     , fGM(gm)
     , fReference(reference)
-    , fConfig(config)
     {}
 
 void ReplayTask::draw() {
     SkPicture picture;
     SkCanvas* canvas = picture.beginRecording(SkScalarCeilToInt(fGM->width()),
                                               SkScalarCeilToInt(fGM->height()),
                                               0 /*flags*/);
 
     canvas->concat(fGM->getInitialTransform());
     fGM->draw(canvas);
     canvas->flush();
 
     picture.endRecording();
 
     SkBitmap bitmap;
-    bitmap.setConfig(fConfig, SkScalarCeilToInt(fGM->width()), SkScalarCeilToInt(fGM->height()));
+    bitmap.setConfig(fReference.config(),
+                     SkScalarCeilToInt(fGM->width()),
+                     SkScalarCeilToInt(fGM->height()));
     bitmap.allocPixels();
     bitmap.eraseColor(0x00000000);
 
     SkCanvas replay(bitmap);
     replay.drawPicture(picture);
     replay.flush();
 
-    const skiagm::GmResultDigest replayDigest(bitmap);
-    if (!replayDigest.equals(fReference)) {
+    const SkAutoLockPixels mine(bitmap), theirs(fReference);
+    if (bitmap.getSize() != fReference.getSize() ||
+        0 != memcmp(bitmap.getPixels(), fReference.getPixels(), bitmap.getSize()))
+    {
         this->fail();
     }
 }
 
 bool ReplayTask::shouldSkip() const {
     return fGM->getFlags() & skiagm::GM::kGPUOnly_Flag ||
            fGM->getFlags() & skiagm::GM::kSkipPicture_Flag;
 }
 
 }  // namespace