[ruby-cvs:71075] nobu:r63984 (trunk): Fix message when `order` was an invalid value

[nobu at ruby-lang.org]

nobu	2018-07-17 10:22:32 +0900 (Tue, 17 Jul 2018)

  New Revision: 63984

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=63984

  Log:
    Fix message when `order` was an invalid value
    
    The symbol that can be used is `:bottom`, not `:down`.
    Ref: https://github.com/ruby/ruby/blob/e39b2cff8ac2dc93b35bd43ffcce3ded8e3b4c25/error.c#L1061
    
    [Fix GH-1916]
    
    From: yuuji.yaginuma <yuuji.yaginuma at gmail.com>

  Modified files:
    trunk/error.c