common.mk: update source tree

* common.mk (after-update): update files under source tree.
  [ruby-core:65840] [Bug #10414]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48099 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* 2014-10-23

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48100 b2dd03c8-39d4-4d8f-98ff-823fe69b080e