replace undoable prop with mutationMode prop (#202)

src/components/RoomDirectory.js

@@ -59,7 +59,7 @@ export const RoomDirectoryBulkDeleteButton = props => (
   <BulkDeleteButton
     {...props}
     label="resources.room_directory.action.erase"
-    undoable={false}
+    mutationMode="pessimistic"
     confirmTitle="resources.room_directory.action.title"
     confirmContent="resources.room_directory.action.content"
     resource="room_directory"

src/components/rooms.js

@@ -315,7 +315,7 @@ const RoomBulkActionButtons = props => (
       {...props}
       confirmTitle="resources.rooms.action.erase.title"
       confirmContent="resources.rooms.action.erase.content"
-      undoable={false}
+      mutationMode="pessimistic"
     />
   </Fragment>
 );

src/components/users.js

@@ -144,7 +144,7 @@ const UserBulkActionButtons = props => (
       {...props}
       label="resources.users.action.erase"
       confirmTitle="resources.users.helper.erase"
-      undoable={false}
+      mutationMode="pessimistic"
     />
   </Fragment>
 );