[wasm] enable wasm structured cloning in specific cases

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
index 6fe6418850cd580284c5de016641fab4a8f8e50d..6976da0190c341c1109e02cf0302c5051123d5ab 100644
--- a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
@@ -90,6 +90,7 @@ V8ScriptValueDeserializer::V8ScriptValueDeserializer(
       m_transferredMessagePorts(options.messagePorts),
       m_blobInfoArray(options.blobInfo) {
   m_deserializer.SetSupportsLegacyWireFormat(true);
+  m_deserializer.SetExpectInlineWasm(options.readWasmFromStream);
 }
 
 v8::Local<v8::Value> V8ScriptValueDeserializer::deserialize() {
@@ -405,4 +406,15 @@ v8::MaybeLocal<v8::Object> V8ScriptValueDeserializer::ReadHostObject(
   return wrapper.As<v8::Object>();
 }
 
+v8::MaybeLocal<v8::WasmCompiledModule>
+V8ScriptValueDeserializer::GetWasmModuleFromId(v8::Isolate* isolate,
+                                               uint32_t id) {
+  if (id < m_serializedScriptValue->wasmModules().size()) {
+    return v8::WasmCompiledModule::FromTransferrableModule(
+        isolate, m_serializedScriptValue->wasmModules()[id]);
+  }
+  CHECK(m_serializedScriptValue->wasmModules().empty());
+  return v8::MaybeLocal<v8::WasmCompiledModule>();

[jbroman, 2017/03/27 18:50:52]

nit: The usual expectation is that functions returning MaybeLocal across the API
boundary throw an exception when they return nothing.

[Mircea Trofin, 2017/03/27 20:52:33]

OK to do so, but I'd wait first for Domenic & Joshua to wrap up the spec.

[jbroman, 2017/03/28 15:27:25]

Please leave a TODO, at least? (Especially since this is more a V8 API than web
API issue.)

+}
+
 }  // namespace blink