SkBitmap and SkPixelRef no longer need lock/unlock

third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1226 matching lines @@
   SkBitmap new_bitmap;
   new_bitmap.allocPixels(
       SkImageInfo::MakeN32Premul(rect.Width(), rect.Height()));
   {
     SkiaPaintCanvas canvas(new_bitmap);
     canvas.clear(SK_ColorTRANSPARENT);
     canvas.translate(-rect.X(), -rect.Y());
     canvas.drawPicture(std::move(new_record));
   }
 
-  old_bitmap.lockPixels();
-  new_bitmap.lockPixels();
   int mismatching_pixels = 0;
   static const int kMaxMismatchesToReport = 50;
   for (int bitmap_y = 0; bitmap_y < rect.Height(); ++bitmap_y) {
     int layer_y = bitmap_y + rect.Y();
     for (int bitmap_x = 0; bitmap_x < rect.Width(); ++bitmap_x) {
       int layer_x = bitmap_x + rect.X();
       SkColor old_pixel = old_bitmap.getColor(bitmap_x, bitmap_y);
       SkColor new_pixel = new_bitmap.getColor(bitmap_x, bitmap_y);
       if (PixelsDiffer(old_pixel, new_pixel) &&
           !tracking->raster_invalidation_region_since_last_paint.Contains(
@@ skipping 11 matching lines @@
           LOG(ERROR) << "and more...";
         }
         ++mismatching_pixels;
         *new_bitmap.getAddr32(bitmap_x, bitmap_y) =
             SkColorSetARGB(0xFF, 0xA0, 0, 0);  // Dark red.
       } else {
         *new_bitmap.getAddr32(bitmap_x, bitmap_y) = SK_ColorTRANSPARENT;
       }
     }
   }
-  old_bitmap.unlockPixels();
-  new_bitmap.unlockPixels();
 
   // Visualize under-invalidations by overlaying the new bitmap (containing red
   // pixels indicating under-invalidations, and transparent pixels otherwise)
   // onto the painting.
   PaintRecorder recorder;
   recorder.beginRecording(rect);
   recorder.getRecordingCanvas()->drawBitmap(new_bitmap, rect.X(), rect.Y());
   sk_sp<PaintRecord> record = recorder.finishRecordingAsPicture();
   GetPaintController().AppendDebugDrawingAfterCommit(
       *this, record, OffsetFromLayoutObjectWithSubpixelAccumulation());
 }
 
 }  // namespace blink
 
 #ifndef NDEBUG
 void showGraphicsLayerTree(const blink::GraphicsLayer* layer) {
   if (!layer) {
     LOG(INFO) << "Cannot showGraphicsLayerTree for (nil).";
     return;
   }
 
   String output = layer->LayerTreeAsText(blink::kLayerTreeIncludesDebugInfo);
   LOG(INFO) << output.Utf8().Data();
 }
 #endif