Revert "Do not include external library sources into packages"

This reverts commit a042043.

(cherry picked from commit 8325094)

Author: nurse

common.mk

@@ -1320,9 +1320,8 @@ up::
 yes::
 no::
 
-EXTRACT_EXTLIBS = extract-extlibs
 after-update:: $(REVISION_H)
-after-update:: $(EXTRACT_EXTLIBS)
+after-update:: extract-extlibs
 after-update:: extract-gems
 
 update-remote:: update-src update-download

tool/make-snapshot

@@ -463,7 +463,6 @@ def package(vcs, rev, destdir, tmp = nil)
       end
       vars.delete("UNICODE_FILES") # for stable branches
       vars["UNICODE_VERSION"] = $unicode_version if $unicode_version
-      vars["EXTRACT_EXTLIBS"] = ""
       args = vars.dup
       mk.gsub!(/@([A-Za-z_]\w*)@/) {args.delete($1); vars[$1] || ENV[$1]}
       mk << commonmk.gsub(/\{\$([^(){}]*)[^{}]*\}/, "").sub(/^revision\.tmp::$/, '\& Makefile')