Backport PR #19876 on branch v3.4.x (FIX: re-order unit conversion and mask array coercion)#20180

QuLogic merged 1 commit intomatplotlib:v3.4.xmatplotlib/matplotlib:v3.4.xfrom

meeseeksmachine:auto-backport-of-pr-19876-on-v3.4.xmeeseeksmachine/matplotlib:auto-backport-of-pr-19876-on-v3.4.xCopy head branch name to clipboard