[wasm] enable wasm structured cloning in specific cases

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

Index: third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.cpp b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.cpp
index 5bfb83bff350d9776245bb18d52f7c1106b2847e..6bc9d9991631b66f9ef21d41f3a808572cc5c50c 100644
--- a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueSerializer.cpp
@@ -49,7 +49,8 @@ V8ScriptValueSerializer::V8ScriptValueSerializer(
       m_serializedScriptValue(SerializedScriptValue::create()),
       m_serializer(m_scriptState->isolate(), this),
       m_transferables(options.transferables),
-      m_blobInfoArray(options.blobInfo) {}
+      m_blobInfoArray(options.blobInfo),
+      m_inlineWasm(options.writeWasmToStream) {}
 
 RefPtr<SerializedScriptValue> V8ScriptValueSerializer::serialize(
     v8::Local<v8::Value> value,
@@ -420,6 +421,21 @@ v8::Maybe<uint32_t> V8ScriptValueSerializer::GetSharedArrayBufferId(
   return v8::Just<uint32_t>(index);
 }
 
+v8::Maybe<uint32_t> V8ScriptValueSerializer::GetWasmModuleTransferId(
+    v8::Isolate* isolate,
+    v8::Local<v8::WasmCompiledModule> module) {
+  if (m_inlineWasm)
+    return v8::Nothing<uint32_t>();
+  // we don't expect scenarios with numerous wasm modules being transferred

[jsbell, 2017/03/22 17:41:07]

Nit: capitalize. Also...  I'm not sure what this comment is telling the reader.
Is it a hint that something is not optimized?

[Mircea Trofin, 2017/03/22 23:31:16]

Done.

+  // around.
+  this->m_serializedScriptValue->wasmModules().push_back(
+      module->GetTransferrableModule());
+  uint32_t size =
+      static_cast<uint32_t>(m_serializedScriptValue->wasmModules().size());
+  DCHECK_GE(size, 1u);
+  return v8::Just(size - 1);
+}
+
 void* V8ScriptValueSerializer::ReallocateBufferMemory(void* oldBuffer,
                                                       size_t size,
                                                       size_t* actualSize) {