chore: add error throwing utility (#19803)

* chore: add error throwing utility

* feedback from review

* DRY out repeated isolate calls

shell/common/error_util.h

@@ -0,0 +1,47 @@
+// Copyright (c) 2019 GitHub, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#ifndef SHELL_COMMON_ERROR_UTIL_H_
+#define SHELL_COMMON_ERROR_UTIL_H_
+
+#include <string>
+
+#include "native_mate/converter.h"
+
+namespace electron {
+
+namespace util {
+
+class ErrorThrower {
+ public:
+  explicit ErrorThrower(v8::Isolate* isolate);
+  ErrorThrower();
+
+  ~ErrorThrower();
+
+  void ThrowError(const std::string& err_msg);
+  void ThrowTypeError(const std::string& err_msg);
+  void ThrowRangeError(const std::string& err_msg);
+  void ThrowReferenceError(const std::string& err_msg);
+  void ThrowSyntaxError(const std::string& err_msg);
+
+ private:
+  v8::Isolate* isolate() const { return isolate_; }
+
+  using ErrorGenerator =
+      v8::Local<v8::Value> (*)(v8::Local<v8::String> err_msg);
+  void Throw(ErrorGenerator gen, const std::string& err_msg) {
+    v8::Local<v8::Value> exception = gen(mate::StringToV8(isolate_, err_msg));
+    if (!isolate_->IsExecutionTerminating())
+      isolate_->ThrowException(exception);
+  }
+
+  v8::Isolate* isolate_;
+};
+
+}  // namespace util
+
+}  // namespace electron
+
+#endif  // SHELL_COMMON_ERROR_UTIL_H_