Ruby

transform_mjit_header.rb: scan by regexp

• tool/transform_mjit_header.rb (find_decl): scan by regexp
  instead of char-by-char loop. return nil when finished.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62213 b2dd03c8-39d4-4d8f-98ff-823fe69b080e