code: private static Map<String, String> convertHeaders(Header[] headers) {
          Map<String, String> result = new HashMap<String, String>(headers.length);
  		for (Header header : headers) {
  			result.put(header.getName(), header.getValue());
  		}
          return result;
      }
docs: Copied from {@link com.android.volley.toolbox.BasicNetwork}
  
  Converts Headers[] to Map<String, String>.