My-Mac:~ admin$ flutter upgrade

    Upgrading Flutter from /Users/admin/Desktop/SDK/flutter...
    error: Your local changes to the following files would be overwritten by merge:
        packages/flutter/lib/src/services/message_codecs.dart
    Please commit your changes or stash them before you merge.
    Aborting
    Updating 2eeeXXXe9..7XXXbf4aX