src/language-js/parser-babel.js/resolvePluginsConflict
function resolvePluginsConflict(
  condition,
  pluginCombinations,
  conflictPlugins
) {
  if (!condition) {
    return pluginCombinations;
  }
  const combinations = [];
  for (const combination of pluginCombinations) {
    for (const plugin of conflictPlugins) {
      combinations.push([...combination, plugin]);
    }
  }
  return combinations;
}