swagger-ui/lib/shred.bundle.js
function(object,names) {
  var keys = (names && names.length>0) ? names : Object.keys($H(object));
  var hash = keys.reduce(function(hash,key) {
    hash[key] = getHeader(object,key);
    return hash;
  },{});
  // Freeze the resulting hash so you don't mistakenly think you're modifying
  // the real headers.
  Object.freeze(hash);
  return hash;
}
function(object,names) {
  var keys = (names && names.length>0) ? names : Object.keys($H(object));
  var hash = keys.reduce(function(hash,key) {
    hash[key] = getHeader(object,key);
    return hash;
  },{});
  // Freeze the resulting hash so you don't mistakenly think you're modifying
  // the real headers.
  Object.freeze(hash);
  return hash;
}
The "real" `getHeader` function: get one or more headers, or all of them if you don't ask for any specifics.