BUG: Need to set the base field apparently and swap promotion
BUG: Need to set the base field apparently and swap promotion

Swapping promotion should not make a difference, but is a bit
closer to what happened before, which should smooth over one
failure in the pandas test-suit.
The swapping probably only affects the promotion of datetime+float
where we have a PR open to disable it in all cases.

mhvk/numpy,endolith/numpy,rgommers/numpy,jakirkham/numpy,madphysicist/numpy,pbrod/numpy,anntzer/numpy,simongibbons/numpy,rgommers/numpy,jakirkham/numpy,charris/numpy,pdebuyl/numpy,anntzer/numpy,mattip/numpy,charris/numpy,numpy/numpy,seberg/numpy,numpy/numpy,simongibbons/numpy,mattip/numpy,jakirkham/numpy,pbrod/numpy,mhvk/numpy,anntzer/numpy,grlee77/numpy,pdebuyl/numpy,numpy/numpy,mhvk/numpy,simongibbons/numpy,pdebuyl/numpy,anntzer/numpy,simongibbons/numpy,madphysicist/numpy,numpy/numpy,pbrod/numpy,simongibbons/numpy,pbrod/numpy,mhvk/numpy,seberg/numpy,grlee77/numpy,pbrod/numpy,madphysicist/numpy,charris/numpy,charris/numpy,endolith/numpy,mattip/numpy,seberg/numpy,grlee77/numpy,pdebuyl/numpy,rgommers/numpy,seberg/numpy,grlee77/numpy,madphysicist/numpy,mattip/numpy,endolith/numpy,rgommers/numpy,grlee77/numpy,madphysicist/numpy,jakirkham/numpy,endolith/numpy,jakirkham/numpy,mhvk/numpy