message: src/processor: improve log message.
diff: @@ -19,9 +19,9 @@ export default function processor(err: AirbrakeError, cb: Callback): void {
  if (!err.__noStack) {
  try {
  frames = ErrorStackParser.parse(err);
  - } catch (_) {
  + } catch (parseErr) {
  if (hasConsole && err.stack) {
  - console.warn('airbrake-js: cannot parse stack:', err.stack);
  + console.warn('ErrorStackParser:', parseErr.toString(), err.stack);
  }
  }
  }
  @@ -59,7 +59,7 @@ export default function processor(err: AirbrakeError, cb: Callback): void {
  msg = String(err);
  }
  - if ((type === '' && msg === '') || backtrace.length === 0) {
  + if (backtrace.length === 0) {
  if (hasConsole) {
  console.warn('airbrake: can not process error:', err.toString());
  }
  