Allow, but do not require, message delivery to devices without active delivery channels

service/src/test/resources/fixtures/current_message_extra_device.json

@@ -10,5 +10,11 @@
         "destinationDeviceId" : 3,
         "content" : "Zm9vYmFyego",
         "timestamp" : 1234
-    }]
+    },
+      {
+        "type" : 1,
+        "destinationDeviceId" : 4,
+        "content" : "Zm9vYmFyego",
+        "timestamp" : 1234
+      }]
 }

service/src/test/resources/fixtures/missing_device_response2.json

@@ -1,4 +1,4 @@
 {
     "missingDevices" : [2],
-    "extraDevices" : [3]
-}
+    "extraDevices" : [4]
+}