Support ImageData cloning in the V8-based structured clone path.

third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.h

Index: third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.h b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.h
index a3e6cc02f64543275468bc473d6bfdd536be534b..781fdc415305d88d2e81917179fa93f9386b1896 100644
--- a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.h
+++ b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.h
@@ -7,7 +7,9 @@
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptState.h"
+#include "bindings/core/v8/SerializationTag.h"
 #include "bindings/core/v8/SerializedScriptValue.h"
+#include "core/CoreExport.h"
 #include "wtf/Allocator.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/RefPtr.h"
@@ -25,18 +27,34 @@ class Transferables;
 //
 // A serializer cannot be used multiple times; it is expected that its serialize
 // method will be invoked exactly once.
-class GC_PLUGIN_IGNORE("https://crbug.com/644725") V8ScriptValueSerializer : public v8::ValueSerializer::Delegate {
+class GC_PLUGIN_IGNORE("https://crbug.com/644725") CORE_EXPORT V8ScriptValueSerializer : public v8::ValueSerializer::Delegate {
     STACK_ALLOCATED();
     WTF_MAKE_NONCOPYABLE(V8ScriptValueSerializer);
 public:
     explicit V8ScriptValueSerializer(RefPtr<ScriptState>);
     RefPtr<SerializedScriptValue> serialize(v8::Local<v8::Value>, Transferables*, ExceptionState&);
 
+protected:
+    // Returns true if the DOM object was successfully written.
+    // If false is returned and no more specific exception is thrown, a generic
+    // DataCloneError message will be used.
+    virtual bool writeDOMObject(ScriptWrappable*, ExceptionState&);
+
+    void writeTag(SerializationTag tag)
+    {
+        uint8_t tagByte = tag;
+        m_serializer.WriteRawBytes(&tagByte, 1);
+    }
+    void writeUint32(uint32_t value) { m_serializer.WriteUint32(value); }
+    void writeUint64(uint64_t value) { m_serializer.WriteUint64(value); }
+    void writeRawBytes(const void* data, size_t size) { m_serializer.WriteRawBytes(data, size); }
+
 private:
     void transfer(Transferables*, ExceptionState&);
 
     // v8::ValueSerializer::Delegate
     void ThrowDataCloneError(v8::Local<v8::String> message) override;
+    v8::Maybe<bool> WriteHostObject(v8::Isolate*, v8::Local<v8::Object> message) override;
 
     RefPtr<ScriptState> m_scriptState;
     RefPtr<SerializedScriptValue> m_serializedScriptValue;