Change device flow's scope into scopes

Author: rayluo

msal/application.py

@@ -245,9 +245,9 @@ def acquire_token_silent(
             logging.debug(
                 "Refresh failed. {error}: {error_description}".format(**response))
 
-    def initiate_device_flow(self, scope=None, **kwargs):
+    def initiate_device_flow(self, scopes=None, **kwargs):
         return self.client.initiate_device_flow(
-            scope=decorate_scope(scope, self.client_id) if scope else None,
+            scope=decorate_scope(scopes or [], self.client_id),
             **kwargs)
 
     def acquire_token_by_device_flow(

tests/test_application.py

@@ -136,7 +136,7 @@ def test_auth_code(self):
         self.assertCacheWorks(result)
 
     def test_device_flow(self):
-        flow = self.app.initiate_device_flow(scope=CONFIG.get("scope"))
+        flow = self.app.initiate_device_flow(scopes=CONFIG.get("scope"))
         logging.warn(flow["message"])
 
         duration = 30