Move V8-based serialization into dedicated classes and add support for ArrayBuffer transfer.

third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp

Index: third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..9561aa556a52229c6c093567ed8accc51ff7cdcf
--- /dev/null
+++ b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
@@ -0,0 +1,81 @@
+// Copyright 2016 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 "bindings/core/v8/serialization/V8ScriptValueDeserializer.h"
+
+#include "bindings/core/v8/ToV8.h"
+#include "core/dom/DOMArrayBuffer.h"
+#include "core/dom/DOMSharedArrayBuffer.h"
+#include "platform/RuntimeEnabledFeatures.h"
+
+namespace blink {
+
+V8ScriptValueDeserializer::V8ScriptValueDeserializer(RefPtr<ScriptState> scriptState, RefPtr<SerializedScriptValue> serializedScriptValue)
+    : m_scriptState(std::move(scriptState))
+    , m_serializedScriptValue(std::move(serializedScriptValue))
+    , m_deserializer(
+        m_scriptState->isolate(),
+        reinterpret_cast<const uint8_t*>(
+            m_serializedScriptValue->data().ensure16Bit(),
+            m_serializedScriptValue->data().characters16()),
+        m_serializedScriptValue->data().length() * 2)
+{
+    DCHECK(RuntimeEnabledFeatures::v8BasedStructuredCloneEnabled());
+    m_deserializer.SetSupportsLegacyWireFormat(true);
+}
+
+v8::Local<v8::Value> V8ScriptValueDeserializer::deserialize()
+{
+#if DCHECK_IS_ON()
+    DCHECK(!m_deserializeInvoked);
+    m_deserializeInvoked = true;
+#endif
+
+    v8::Isolate* isolate = m_scriptState->isolate();
+    v8::EscapableHandleScope scope(isolate);
+    v8::TryCatch tryCatch(isolate);
+    v8::Local<v8::Context> context = m_scriptState->context();
+
+    bool readHeader;
+    if (!m_deserializer.ReadHeader().To(&readHeader))
+        return v8::Null(isolate);
+    DCHECK(readHeader);
+    m_version = m_deserializer.GetWireFormatVersion();
+
+    // Prepare to transfer the provided transferables.
+    transfer();
+
+    v8::Local<v8::Value> value;
+    if (!m_deserializer.ReadValue(context).ToLocal(&value))
+        return v8::Null(isolate);
+    return scope.Escape(value);
+}
+
+void V8ScriptValueDeserializer::transfer()
+{
+    v8::Isolate* isolate = m_scriptState->isolate();
+    v8::Local<v8::Context> context = m_scriptState->context();
+    v8::Local<v8::Object> creationContext = context->Global();
+
+    // Transfer array buffers.
+    if (auto* arrayBufferContents = m_serializedScriptValue->getArrayBufferContentsArray()) {
+        for (unsigned i = 0; i < arrayBufferContents->size(); i++) {
+            WTF::ArrayBufferContents& contents = arrayBufferContents->at(i);
+            if (contents.isShared()) {
+                DOMSharedArrayBuffer* arrayBuffer = DOMSharedArrayBuffer::create(contents);
+                v8::Local<v8::Value> wrapper = toV8(arrayBuffer, creationContext, isolate);
+                DCHECK(wrapper->IsSharedArrayBuffer());
+                m_deserializer.TransferSharedArrayBuffer(
+                    i, v8::Local<v8::SharedArrayBuffer>::Cast(wrapper));
+            } else {
+                DOMArrayBuffer* arrayBuffer = DOMArrayBuffer::create(contents);
+                v8::Local<v8::Value> wrapper = toV8(arrayBuffer, creationContext, isolate);
+                DCHECK(wrapper->IsArrayBuffer());
+                m_deserializer.TransferArrayBuffer(i, v8::Local<v8::ArrayBuffer>::Cast(wrapper));
+            }
+        }
+    }
+}
+
+} // namespace blink