Fix bug when defining primitive projections mixing defined and abstracts fields.
Fix bug when defining primitive projections mixing defined and abstracts fields.

TheTypoMaster/coq,ejgallego/coq,ale-f/coq,TOSPIO/coq,mlasson/coq,coq/coq,aspiwack/coq,Ptival/coq,mattam82/coq,jpdeplaix/coq,gmalecha/coq,pirapira/coq2rust,TheTypoMaster/coq,8l/coq,Matafou/coq,Zimmi48/coq,mattam82/coq,maximedenes/coq,Ptival/coq,ejgallego/coq,william-lawvere/coq,ppedrot/coq,silene/coq,shindere/coq,pirapira/coq2rust,Zimmi48/coq,JasonGross/coq,TOSPIO/coq,mattam82/coq,letouzey/coq-wip,gares/coq,SkySkimmer/coq,amintimany/coq,letouzey/coq-wip,8l/coq,jpdeplaix/coq,JasonGross/coq,william-lawvere/coq,Lionel-Rieg/coq,pirapira/coq2rust,aspiwack/coq,barras/coq,silene/coq,TOSPIO/coq,shindere/coq,maximedenes/coq,silene/coq,8l/coq,amintimany/coq,ejgallego/coq,letouzey/coq-wip,SkySkimmer/coq,coq/coq,asr/coq,amintimany/coq,TheTypoMaster/coq,aspiwack/coq,Matafou/coq,herbelin/github-coq,shindere/coq,gares/coq,jpdeplaix/coq,william-lawvere/coq,asr/coq,Ptival/coq,JasonGross/coq,gares/coq,gmalecha/coq,maximedenes/coq,SkySkimmer/coq,herbelin/github-coq,gares/coq,Lionel-Rieg/coq,barras/coq,Zimmi48/coq,barras/coq,mlasson/coq,SkySkimmer/coq,letouzey/coq-wip,herbelin/github-coq,gares/coq,ppedrot/coq,ejgallego/coq,coq/coq,asr/coq,JasonGross/coq,letouzey/coq-wip,maximedenes/coq,gmalecha/coq,Lionel-Rieg/coq,mlasson/coq,Matafou/coq,coq/coq,maximedenes/coq,ppedrot/coq,Zimmi48/coq,ale-f/coq,ale-f/coq,ppedrot/coq,ppedrot/coq