// This gets rid of migrations which try to use a non-existent source
// plugin. The common case for this is if the source plugin has, or
// specifies, a non-existent provider.
// This gets rid of migrations which try to use a non-existent source
// plugin. The common case for this is if the source plugin has, or
// specifies, a non-existent provider.
// This gets rid of migrations with explicit providers set if one of the
// providers do not exist before we try to use a potentially non-existing
// deriver. This is a rare case.
// This gets rid of migrations with explicit providers set if one of the
// providers do not exist before we try to use a potentially non-existing
// deriver. This is a rare case.