Revert "Correctly return status code 400 on ValueError when validating the object."
Revert "Correctly return status code 400 on ValueError when validating the object."

This reverts commit 8f59985390926285eb4a4ef72530f6170ccbbe12.

Plexxi/st2,peak6/st2,nzlosh/st2,pixelrebel/st2,Plexxi/st2,pixelrebel/st2,nzlosh/st2,emedvedev/st2,lakshmi-kannan/st2,peak6/st2,lakshmi-kannan/st2,dennybaa/st2,punalpatel/st2,dennybaa/st2,punalpatel/st2,StackStorm/st2,tonybaloney/st2,nzlosh/st2,tonybaloney/st2,emedvedev/st2,armab/st2,punalpatel/st2,armab/st2,lakshmi-kannan/st2,armab/st2,Plexxi/st2,StackStorm/st2,StackStorm/st2,nzlosh/st2,pixelrebel/st2,emedvedev/st2,peak6/st2,dennybaa/st2,Plexxi/st2,tonybaloney/st2,StackStorm/st2