Revert of [wasm] Refactor function name table and lookup

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index 872434606f6d935c418c6b0a09558821c340f575..035a626acd2eff1ba4439ae8b322a2fe3ba93af6 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -605,9 +605,16 @@
         factory()->NewJSObject(isolate_->object_function());
 
     if (!function_key_.is_null()) {
-      Handle<String> name = wasm::GetWasmFunctionName(
-          isolate_, handle(frame->wasm_obj(), isolate_),
-          frame->function_index());
+      Object* wasm_object = frame->wasm_obj();
+      Handle<String> name;
+      if (!wasm_object->IsUndefined(isolate_)) {
+        Handle<JSObject> wasm = handle(JSObject::cast(wasm_object));
+        wasm::GetWasmFunctionName(wasm, frame->function_index())
+            .ToHandle(&name);
+      }
+      if (name.is_null()) {
+        name = isolate_->factory()->NewStringFromStaticChars("<WASM UNNAMED>");
+      }
       JSObject::AddProperty(stack_frame, function_key_, name, NONE);
     }
     // Encode the function index as line number.