I'm planning on building a shower with a typical plastic shower pan liner: https://images.homedepot-static.com/productImages/8e45b9f6-39cd-4f9a-ba89-c86cd5071314/svn/oatey-shower-bases-pans-41631-64_1000.jpg. The walls will be water and mold resistant drywall with a roll-on waterproof membrane.
I'm trying to decide how the drywall will meet the plastic shower liner. Should I install the plastic shower pan liner first, then the mold resistant drywall so that water that might get to the drywall will "roll" onto the shower pan liner? Or should I plan on putting up the drywall first, then the shower pan liner taking care to seal the shower pan liner to the drywall so that no water gets between them?