Revert "upgrade gunicorn 19.0 and make upgrade"

This reverts commit f6c215ae5b.

common/djangoapps/track/views/__init__.py

@@ -96,8 +96,6 @@ def server_track(request, event_type, event, page=None):
     except:
         username = "anonymous"
 
-    host_header = 'HTTP_HOST' if request is not None and 'HTTP_HOST' in request.META else 'SERVER_NAME'
-
     # define output:
     event = {
         "username": username,
@@ -110,7 +108,7 @@ def server_track(request, event_type, event, page=None):
         "agent": _get_request_header(request, 'HTTP_USER_AGENT').decode('latin1'),
         "page": page,
         "time": datetime.datetime.utcnow().replace(tzinfo=pytz.utc),
-        "host": _get_request_header(request, host_header),
+        "host": _get_request_header(request, 'SERVER_NAME'),
         "context": eventtracker.get_tracker().resolve_context(),
     }
 

common/djangoapps/util/views.py

@@ -388,8 +388,6 @@ def get_feedback_form_context(request):
 
     context["additional_info"] = {}
 
-    host_header = 'HTTP_HOST' if request is not None and 'HTTP_HOST' in request.META else 'SERVER_NAME'
-
     if request.user.is_authenticated:
         context["realname"] = request.user.profile.name
         context["email"] = request.user.email
@@ -399,7 +397,7 @@ def get_feedback_form_context(request):
         context["email"] = request.POST["email"]
 
     for header, pretty in [("HTTP_REFERER", "Page"), ("HTTP_USER_AGENT", "Browser"), ("REMOTE_ADDR", "Client IP"),
-                           (host_header, "Host")]:
+                           ("SERVER_NAME", "Host")]:
         context["additional_info"][pretty] = request.META.get(header)
 
     context["support_email"] = configuration_helpers.get_value('email_from_address', settings.DEFAULT_FROM_EMAIL)