merge revision(s) r47683: [Backport #10281]

	array.c: GC guard

	* array.c (rb_ary_splice): prevent replacing array from GC.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@47701 b2dd03c8-39d4-4d8f-98ff-823fe69b080e