[downloader/http] Add ability to pass downloader options via info dict

youtube_dl/downloader/http.py

@@ -45,6 +45,7 @@ class DownloadContext(dict):
 
         is_test = self.params.get('test', False)
         chunk_size = self._TEST_FILE_SIZE if is_test else (
+            info_dict.get('downloader_options', {}).get('http_chunk_size') or
             self.params.get('http_chunk_size') or 0)
 
         ctx.open_mode = 'wb'

youtube_dl/extractor/common.py

@@ -174,6 +174,8 @@ class InfoExtractor(object):
                                  width : height ratio as float.
                     * no_resume  The server does not support resuming the
                                  (HTTP or RTMP) download. Boolean.
+                    * downloader_options  A dictionary of downloader options as
+                                 described in FileDownloader
 
     url:            Final video URL.
     ext:            Video filename extension.