old_contents: 
  import React from 'react';
  import PureComponent from 'react-pure-render/component';
  import ReactDOM from 'react-dom';
  
  import Qustom from '../../src/index';
  
  
  class App extends PureComponent {
      render() {
          return (
              <div>
                  <Qustom {...this.props} />
              </div>
          );
      }
  }
  
  function getParameterByName(targetName) {
      const url = window.location.href;
      const name = targetName.replace(/[\[\]]/g, '\\$&');
      const regex = new RegExp(`[?&]${name}(=([^&#]*)|&|#|$)`);
      const results = regex.exec(url);
      if (!results) return null;
      if (!results[2]) return '';
      return decodeURIComponent(results[2].replace(/\+/g, ' '));
  }
  
  function initApp() {
      let view;
      if (!getParameterByName('accountid') && !getParameterByName('surveyid')) {
          view = (<h1 className="error">Survey ID and Account ID are required!</h1>);
      } else if (!getParameterByName('surveyid')) {
          view = (<h1 className="error">Survey ID is required!</h1>);
      } else if (!getParameterByName('accountid')) {
          view = (<h1 className="error">Account ID is required!</h1>);
      } else {
          const props = {
              accountid: getParameterByName('accountid') || 'context.authorizer.principalId',
              surveyid: getParameterByName('surveyid') || '759e7930-3219-11e6-b8fc-ed3df7fb1eab',
              type: getParameterByName('type') || 'default', // type=default/embedded
              locale: getParameterByName('locale') || '', // sync with product or no need
              // preview mode does not send out feedback
              preview: getParameterByName('preview') || false
          };
          view = (<App {...props} />);
      }
      ReactDOM.render(
          view,
          document.getElementById('main')
      );
  }
  
  initApp();
  
  if (module.hot) {
      module.hot.accept();
  }
  
new_contents: 
  import React from 'react';
  import PureComponent from 'react-pure-render/component';
  import ReactDOM from 'react-dom';
  
  import Qustom from '../../src/index';
  
  
  class App extends PureComponent {
      render() {
          return (
              <div>
                  <Qustom {...this.props} />
              </div>
          );
      }
  }
  
  function getParameterByName(targetName) {
      const url = window.location.href;
      const name = targetName.replace(/[\[\]]/g, '\\$&');
      const regex = new RegExp(`[?&]${name}(=([^&#]*)|&|#|$)`);
      const results = regex.exec(url);
      if (!results) return null;
      if (!results[2]) return '';
      return decodeURIComponent(results[2].replace(/\+/g, ' '));
  }
  
  function initApp() {
      let view;
      if (!getParameterByName('accountid') && !getParameterByName('surveyid')) {
          view = (<h1 className="error">Survey ID and Account ID are required!</h1>);
      } else if (!getParameterByName('surveyid')) {
          view = (<h1 className="error">Survey ID is required!</h1>);
      } else if (!getParameterByName('accountid')) {
          view = (<h1 className="error">Account ID is required!</h1>);
      } else {
          // handle en to en-US
          let locale = getParameterByName('locale') || '';
          locale = locale === 'en' ? 'en-US' : locale;
          const props = {
              accountid: getParameterByName('accountid') || 'context.authorizer.principalId',
              surveyid: getParameterByName('surveyid') || '759e7930-3219-11e6-b8fc-ed3df7fb1eab',
              type: getParameterByName('type') || 'default', // type=default/embedded
              locale: locale, // sync with product or no need
              // preview mode does not send out feedback
              preview: getParameterByName('preview') || false
          };
          view = (<App {...props} />);
      }
      ReactDOM.render(
          view,
          document.getElementById('main')
      );
  }
  
  initApp();
  
  if (module.hot) {
      module.hot.accept();
  }
  
subject: Set en locale to be en-US