Use instance type in Object::IsErrorObject().

test/cctest/wasm/test-wasm-trap-position.cc

Index: test/cctest/wasm/test-wasm-trap-position.cc
diff --git a/test/cctest/wasm/test-wasm-trap-position.cc b/test/cctest/wasm/test-wasm-trap-position.cc
index 5a7d2c2fe9c5f4a28ddcccfdfa3896250706a33e..30f5d48a07be40a98b82a5218b0489fcdffe1c7b 100644
--- a/test/cctest/wasm/test-wasm-trap-position.cc
+++ b/test/cctest/wasm/test-wasm-trap-position.cc
@@ -38,10 +38,10 @@ struct ExceptionInfo {
 };
 
 template <int N>
-void CheckExceptionInfos(Isolate* isolate, Handle<Object> exc,
+void CheckExceptionInfos(Handle<Object> exc,
                          const ExceptionInfo (&excInfos)[N]) {
   // Check that it's indeed an Error object.
-  CHECK(Object::IsErrorObject(isolate, exc));
+  CHECK(exc->IsJSError());
 
   // Extract stack frame from the exception.
   Local<v8::Value> localExc = Utils::ToLocal(exc);
@@ -93,8 +93,7 @@ TEST(Unreachable) {
       {"<WASM UNNAMED>", static_cast<int>(wasm_index), 2},  // --
       {"callFn", 1, 24}                                     // --
   };
-  CheckExceptionInfos(isolate, maybe_exc.ToHandleChecked(),
-                      expected_exceptions);
+  CheckExceptionInfos(maybe_exc.ToHandleChecked(), expected_exceptions);
 }
 
 // Trigger a trap for loading from out-of-bounds.
@@ -136,6 +135,5 @@ TEST(IllegalLoad) {
       {"<WASM UNNAMED>", static_cast<int>(wasm_index_2), 3},  // --
       {"callFn", 1, 24}                                       // --
   };
-  CheckExceptionInfos(isolate, maybe_exc.ToHandleChecked(),
-                      expected_exceptions);
+  CheckExceptionInfos(maybe_exc.ToHandleChecked(), expected_exceptions);
 }