Make WebTaskRunner ThreadSafeRefCounted

third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.cpp

 /*
  * Copyright (c) 2013, Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 239 matching lines @@
 void ImageBitmapFactories::ImageBitmapLoader::scheduleAsyncImageBitmapDecoding(
     DOMArrayBuffer* arrayBuffer) {
   // For a 4000*4000 png image where each 10*10 tile is filled in by a random
   // RGBA value, the byteLength is around 2M, and it typically takes around
   // 4.5ms to decode on a current model of Linux desktop.
   const int longTaskByteLengthThreshold = 2000000;
   BackgroundTaskRunner::TaskSize taskSize =
       BackgroundTaskRunner::TaskSizeShortRunningTask;
   if (arrayBuffer->byteLength() >= longTaskByteLengthThreshold)
     taskSize = BackgroundTaskRunner::TaskSizeLongRunningTask;
-  WebTaskRunner* taskRunner =
+  RefPtr<WebTaskRunner> taskRunner =
       Platform::current()->currentThread()->getWebTaskRunner();
   BackgroundTaskRunner::postOnBackgroundThread(
       BLINK_FROM_HERE,
       crossThreadBind(
           &ImageBitmapFactories::ImageBitmapLoader::decodeImageOnDecoderThread,
-          wrapCrossThreadPersistent(this), crossThreadUnretained(taskRunner),
+          wrapCrossThreadPersistent(this), std::move(taskRunner),
           wrapCrossThreadPersistent(arrayBuffer), m_options.premultiplyAlpha(),
           m_options.colorSpaceConversion()),
       taskSize);
 }
 
 void ImageBitmapFactories::ImageBitmapLoader::decodeImageOnDecoderThread(
-    WebTaskRunner* taskRunner,
+    RefPtr<WebTaskRunner> taskRunner,
     DOMArrayBuffer* arrayBuffer,
     const String& premultiplyAlphaOption,
     const String& colorSpaceConversionOption) {
   ASSERT(!isMainThread());
 
   ImageDecoder::AlphaOption alphaOp = ImageDecoder::AlphaPremultiplied;
   if (premultiplyAlphaOption == "none")
     alphaOp = ImageDecoder::AlphaNotPremultiplied;
   ImageDecoder::ColorSpaceOption colorSpaceOp =
       ImageDecoder::ColorSpaceTransformed;
@@ skipping 36 matching lines @@
   }
   m_factory->didFinishLoading(this);
 }
 
 DEFINE_TRACE(ImageBitmapFactories::ImageBitmapLoader) {
   visitor->trace(m_factory);
   visitor->trace(m_resolver);
 }
 
 }  // namespace blink