Add missing tests for download snippet
Add missing tests for download snippet

ref: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6720

t-zuehlsdorff/gitlabhq,stoplightio/gitlabhq,daiyu/gitlab-zh,daiyu/gitlab-zh,dreampet/gitlab,daiyu/gitlab-zh,darkrasid/gitlabhq,iiet/iiet-git,dreampet/gitlab,openwide-java/gitlabhq,openwide-java/gitlabhq,dplarson/gitlabhq,mmkassem/gitlabhq,jirutka/gitlabhq,darkrasid/gitlabhq,axilleas/gitlabhq,daiyu/gitlab-zh,LUMC/gitlabhq,darkrasid/gitlabhq,stoplightio/gitlabhq,htve/GitlabForChinese,mmkassem/gitlabhq,t-zuehlsdorff/gitlabhq,axilleas/gitlabhq,htve/GitlabForChinese,dreampet/gitlab,jirutka/gitlabhq,iiet/iiet-git,darkrasid/gitlabhq,dreampet/gitlab,axilleas/gitlabhq,mmkassem/gitlabhq,dplarson/gitlabhq,t-zuehlsdorff/gitlabhq,jirutka/gitlabhq,LUMC/gitlabhq,stoplightio/gitlabhq,axilleas/gitlabhq,mmkassem/gitlabhq,t-zuehlsdorff/gitlabhq,jirutka/gitlabhq,openwide-java/gitlabhq,LUMC/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,openwide-java/gitlabhq,iiet/iiet-git,htve/GitlabForChinese,htve/GitlabForChinese,dplarson/gitlabhq,LUMC/gitlabhq,dplarson/gitlabhq