Follow up to the activity in Issue SeleniumHQ#6452

Sets proper 'Accept' request header so that Python bindings work with some old WebDriver implementations that reply 404 to requests with no 'Accept' set.

Signed-off-by: Luke Inman-Semerau <luke.semerau@gmail.com>

py/selenium/webdriver/remote/remote_connection.py

@@ -368,7 +368,8 @@ def _request(self, url, data=None, method=None):
         headers["Connection"] = "Keep-Alive"
         headers[method] = parsed_url.path
         headers["User-Agent"] = "Python http auth"
-        headers["Content-type"] = "text/html;charset=\"UTF-8\""
+        headers["Content-type"] = "application/json;charset=\"UTF-8\""
+        headers["Accept"] = "application/json"
         headers["Connection"] = "keep-alive"
 
         # for basic auth