old_contents: /**
   * Create a blob builder even when vendor prefixes exist
   */
  
  var BlobBuilder = window.BlobBuilder
    || window.WebKitBlobBuilder
    || window.MSBlobBuilder
    || window.MozBlobBuilder;
  
  /**
   * Check if Blob constructor is supported
   */
  
  var blobSupported = (function() {
    try {
      var b = new Blob(['hi']);
      return b.size == 2;
    } catch(e) {
      return false;
    }
  })();
  
  /**
   * Check if BlobBuilder is supported
   */
  
  var blobBuilderSupported = BlobBuilder
    && BlobBuilder.prototype.append
    && BlobBuilder.prototype.getBlob;
  
  function BlobBuilderConstructor(ary, options) {
    options = options || {};
  
    var bb = new BlobBuilder();
    for (var i = 0; i < ary.length; i++) {
      bb.append(ary[i]);
    }
    return (options.type) ? bb.getBlob(options.type) : bb.getBlob();
  };
  
  module.exports = (function() {
    if (blobSupported) {
      return window.Blob;
    } else if (blobBuilderSupported) {
      return BlobBuilderConstructor;
    } else {
      return undefined;
    }
  })();
  
new_contents: /**
   * Create a blob builder even when vendor prefixes exist
   */
  
  var BlobBuilder = global.BlobBuilder
    || global.WebKitBlobBuilder
    || global.MSBlobBuilder
    || global.MozBlobBuilder;
  
  /**
   * Check if Blob constructor is supported
   */
  
  var blobSupported = (function() {
    try {
      var b = new Blob(['hi']);
      return b.size == 2;
    } catch(e) {
      return false;
    }
  })();
  
  /**
   * Check if BlobBuilder is supported
   */
  
  var blobBuilderSupported = BlobBuilder
    && BlobBuilder.prototype.append
    && BlobBuilder.prototype.getBlob;
  
  function BlobBuilderConstructor(ary, options) {
    options = options || {};
  
    var bb = new BlobBuilder();
    for (var i = 0; i < ary.length; i++) {
      bb.append(ary[i]);
    }
    return (options.type) ? bb.getBlob(options.type) : bb.getBlob();
  };
  
  module.exports = (function() {
    if (blobSupported) {
      return global.Blob;
    } else if (blobBuilderSupported) {
      return BlobBuilderConstructor;
    } else {
      return undefined;
    }
  })();
  
subject: Use global instead of window