Make OffscreenCanvas Transferable

third_party/WebKit/Source/bindings/core/v8/SerializedScriptValue.cpp

Index: third_party/WebKit/Source/bindings/core/v8/SerializedScriptValue.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/SerializedScriptValue.cpp b/third_party/WebKit/Source/bindings/core/v8/SerializedScriptValue.cpp
index 06080d9946bd787b1658361e7d444c96823ee809..fe179c9cede3a8dd9d18aec16168c83c27eb5911 100644
--- a/third_party/WebKit/Source/bindings/core/v8/SerializedScriptValue.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/SerializedScriptValue.cpp
@@ -36,6 +36,7 @@
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/ScriptValueSerializer.h"
 #include "bindings/core/v8/SerializedScriptValueFactory.h"
+#include "bindings/core/v8/TransferableExtractor.h"
 #include "bindings/core/v8/Transferables.h"
 #include "bindings/core/v8/V8ArrayBuffer.h"
 #include "bindings/core/v8/V8ImageBitmap.h"
@@ -225,6 +226,7 @@ bool SerializedScriptValue::extractTransferables(v8::Isolate* isolate, v8::Local
     }
 
     v8::Local<v8::Object> transferableArray = v8::Local<v8::Object>::Cast(value);
+    Vector<OwnPtr<TransferableExtractor>> extractors;
 
     // Validate the passed array of transferables.
     for (unsigned i = 0; i < length; ++i) {
@@ -236,6 +238,15 @@ bool SerializedScriptValue::extractTransferables(v8::Isolate* isolate, v8::Local
             exceptionState.throwTypeError("Value at index " + String::number(i) + " is an untransferable " + (transferableObject->IsUndefined() ? "'undefined'" : "'null'") + " value.");
             return false;
         }
+        bool extractorDoneFlag = false;
+        for (const auto& ex : TransferableExtractor::getExtractors()) {
+            if (ex->extract(transferableObject, isolate, transferables, exceptionState, i)) {
+                extractorDoneFlag = true;
+                break;
+            }
+        }
+        if (extractorDoneFlag)
+            break;
         // Validation of Objects implementing an interface, per WebIDL spec 4.1.15.
         if (V8MessagePort::hasInstance(transferableObject, isolate)) {
             MessagePort* port = V8MessagePort::toImpl(v8::Local<v8::Object>::Cast(transferableObject));