array.c: speedup Array#unshift by using space in shared array
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37584 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
array.c: speedup Array#unshift by using space in shared array
[Feature #6638]
is enough space then try unshift values directly into shared
array.
enough room for future #unshifts, and then insert into shared
array.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37584 b2dd03c8-39d4-4d8f-98ff-823fe69b080e