Bug 1622682 : removed unused imports and variables. r=sylvestre

Differential Revision: https://phabricator.services.mozilla.com/D67011

--HG--
extra : moz-landing-system : lando

.flake8

@@ -9,7 +9,6 @@ exclude =
     dom/browser-element,
     dom/canvas,
     dom/encoding,
-    dom/security,
     dom/websocket,
     gfx/tests,
     ipc/ipdl/ipdl,

dom/security/test/csp/file_upgrade_insecure_wsh.py

@@ -1,7 +1,8 @@
-from mod_pywebsocket import msgutil
+
 
 def web_socket_do_extra_handshake(request):
-  pass
+    pass
+
 
 def web_socket_transfer_data(request):
-  pass
+    pass

dom/security/test/csp/file_websocket_self_wsh.py

@@ -1,7 +1,8 @@
-from mod_pywebsocket import msgutil
+
 
 def web_socket_do_extra_handshake(request):
-  pass
+    pass
+
 
 def web_socket_transfer_data(request):
-  pass
+    pass

dom/security/test/https-only/file_upgrade_insecure_wsh.py

@@ -1,7 +1,8 @@
-from mod_pywebsocket import msgutil
+
 
 def web_socket_do_extra_handshake(request):
-  pass
+    pass
+
 
 def web_socket_transfer_data(request):
-  pass
+    pass

dom/security/test/mixedcontentblocker/file_main_bug803225_websocket_wsh.py

@@ -1,7 +1,8 @@
-from mod_pywebsocket import msgutil
+
 
 def web_socket_do_extra_handshake(request):
-  pass
+    pass
+
 
 def web_socket_transfer_data(request):
-  resp = ""
+    pass