amend r88019 & r87971 for when e.g., ..@Generic is the group name

git-svn-id: https://svn.r-project.org/R/trunk@88055 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: maechler

src/library/methods/R/MethodsListClass.R

@@ -125,7 +125,7 @@ loadMethod <- function(method, fname, envir) method
               function(method, fname, envir) {
                   assign(".target",  method@target,  envir = envir)
                   assign(".defined", method@defined, envir = envir)
-                  assign(".Generic", method@generic, envir = envir)
+                  assign(".Generic", if(missing(fname)) method@generic else fname, envir = envir)
                   assign(".Method",  method, envir = envir)
                   method
               }, where = envir)