Make ImageBitmap Transferable

third_party/WebKit/Source/core/frame/ImageBitmap.cpp

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/frame/ImageBitmap.h"
 
 #include "core/html/HTMLCanvasElement.h"
 #include "core/html/HTMLVideoElement.h"
 #include "core/html/ImageData.h"
@@ skipping 163 matching lines @@
     IntRect normalizedCropRect = normalizeRect(cropRect);
     return adoptRefWillBeNoop(new ImageBitmap(bitmap, normalizedCropRect));
 }
 
 PassRefPtrWillBeRawPtr<ImageBitmap> ImageBitmap::create(Image* image, const IntRect& cropRect)
 {
     IntRect normalizedCropRect = normalizeRect(cropRect);
     return adoptRefWillBeNoop(new ImageBitmap(image, normalizedCropRect));
 }
 
+void ImageBitmap::neuter()

[Justin Novosad, 2015/10/24 03:04:48]

I don't see why neuter and transfer need to be separate functions. Semantically
transfer means make a shallow copy and neuter the original. Right now transfer()
only does the copy part, which is misleading. IMHO we should just have one
method named 'transfer' that does all the work. If there is a legitimate reason
to have both methods, then they should be named 'neuter' and 'shallowCopy'.

[xidachen, 2015/10/24 20:36:25]

That makes perfect sense. They are now merged into one function "transfer".

+{
+    if (m_imageElement)
+        m_imageElement.clear();
+    if (m_bitmap)
+        m_bitmap.clear();
+}
+
+PassRefPtrWillBeRawPtr<ImageBitmap> ImageBitmap::transfer()
+{
+    return adoptRefWillBeNoop(new ImageBitmap(this, m_cropRect));
+}
+
 void ImageBitmap::notifyImageSourceChanged()
 {
     m_bitmap = cropImage(m_imageElement->cachedImage()->image(), m_cropRect);
     m_bitmapOffset = IntPoint();
     m_imageElement = nullptr;
 }
 
 PassRefPtr<Image> ImageBitmap::bitmapImage() const
 {
     ASSERT((m_imageElement || m_bitmap || !m_bitmapRect.width() || !m_bitmapRect.height()) && (!m_imageElement || !m_bitmap));
@@ skipping 26 matching lines @@
     return FloatSize(width(), height());
 }
 
 DEFINE_TRACE(ImageBitmap)
 {
     visitor->trace(m_imageElement);
     ImageLoaderClient::trace(visitor);
 }
 
 } // namespace blink