Move DOMArrayBuffer, DOMArrayBufferViews and DataView to the heap.

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

Index: third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.cpp
diff --git a/third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.cpp b/third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.cpp
index 2bda28d22764fee3abb96059c5f7c175e588a1e5..77c2e8c50bd6d22f91ac79a7f28990a7f4af5f8e 100644
--- a/third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.cpp
+++ b/third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.cpp
@@ -191,11 +191,12 @@ void ImageBitmapFactories::ImageBitmapLoader::rejectPromise()
 
 void ImageBitmapFactories::ImageBitmapLoader::didFinishLoading()
 {
-    if (!m_loader.arrayBufferResult()) {
+    DOMArrayBuffer* arrayBuffer = m_loader.arrayBufferResult();

[sof, 2016/04/10 17:32:28]

As FileReaderLoader re-creates a DOMArrayBuffer each time arrayBufferResult() is
called, it isn't very nice to call it repeatedly. Moreover, as
arrayBufferResult() is also called on the decoder thread, it is somewhat untidy
to adjust the underlying ref count of ArrayBufferBuilder's ArrayBuffer from
another thread.  Hence, arrange for the DOMArrayBuffer to be created on the main
thread and passed in to the operation on the decoder thread.

+    if (!arrayBuffer) {
         rejectPromise();
         return;
     }
-    scheduleAsyncImageBitmapDecoding();
+    scheduleAsyncImageBitmapDecoding(arrayBuffer);
 }
 
 void ImageBitmapFactories::ImageBitmapLoader::didFail(FileError::ErrorCode)
@@ -203,21 +204,23 @@ void ImageBitmapFactories::ImageBitmapLoader::didFail(FileError::ErrorCode)
     rejectPromise();
 }
 
-void ImageBitmapFactories::ImageBitmapLoader::scheduleAsyncImageBitmapDecoding()
+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 = (m_loader.arrayBufferResult()->byteLength() >= longTaskByteLengthThreshold) ? BackgroundTaskRunner::TaskSizeLongRunningTask : BackgroundTaskRunner::TaskSizeShortRunningTask;
+    BackgroundTaskRunner::TaskSize taskSize = BackgroundTaskRunner::TaskSizeShortRunningTask;
+    if (arrayBuffer->byteLength() >= longTaskByteLengthThreshold)
+        taskSize = BackgroundTaskRunner::TaskSizeLongRunningTask;
     WebTaskRunner* taskRunner = Platform::current()->currentThread()->getWebTaskRunner();
-    BackgroundTaskRunner::postOnBackgroundThread(BLINK_FROM_HERE, threadSafeBind(&ImageBitmapFactories::ImageBitmapLoader::decodeImageOnDecoderThread, AllowCrossThreadAccess(this), AllowCrossThreadAccess(taskRunner)), taskSize);
+    BackgroundTaskRunner::postOnBackgroundThread(BLINK_FROM_HERE, threadSafeBind(&ImageBitmapFactories::ImageBitmapLoader::decodeImageOnDecoderThread, AllowCrossThreadAccess(this), AllowCrossThreadAccess(taskRunner), AllowCrossThreadAccess(arrayBuffer)), taskSize);
 }
 
-void ImageBitmapFactories::ImageBitmapLoader::decodeImageOnDecoderThread(WebTaskRunner* taskRunner)
+void ImageBitmapFactories::ImageBitmapLoader::decodeImageOnDecoderThread(WebTaskRunner* taskRunner, DOMArrayBuffer* arrayBuffer)
 {
     ASSERT(!isMainThread());
-    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::create((char*)m_loader.arrayBufferResult()->data(), static_cast<size_t>(m_loader.arrayBufferResult()->byteLength()));
+    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::create(static_cast<char*>(arrayBuffer->data()), static_cast<size_t>(arrayBuffer->byteLength()));
 
     ImageDecoder::AlphaOption alphaOp = ImageDecoder::AlphaPremultiplied;
     if (m_options.premultiplyAlpha() == "none")