merge revision(s) r45399,r45400,r46036,r46037: [Backport #416]

	vm.c: merge code

	* vm.c (m_core_hash_from_ary, m_core_hash_merge_ary): merge
  duplicated code.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@46628 b2dd03c8-39d4-4d8f-98ff-823fe69b080e