Do not add \inputencoding when installing LaTeX help and

using default UTF-8 encoding.
Fixes issue for R CMD check --install-args="--latex" reported on the
R-devel mailing list.
Thanks to Peter Ruckdeschel and Ivan Krylov.

git-svn-id: https://svn.r-project.org/R/trunk@87598 00db46b3-68df-0310-9c12-caf00c1e9a41

src/library/tools/R/install.R

@@ -3132,7 +3132,8 @@ if(FALSE) {
             if (!file_test("-f", ff) || file_test("-nt", f, ff)) {
                 showtype(type)
                 .convert(Rd2latex(Rd, ff, defines = NULL,
-                                  outputEncoding = outenc))
+                                  outputEncoding = outenc,
+                                  writeEncoding = (outenc != "UTF-8")))
             }
         }
         if ("example" %in% types) {