It's declared in the later versions of the patch but here it was not and It was causing compilation errors and adding the function manually from the later version causes seg faults. From what I see it's not required in dwl 0.7 with wlroots 0.18 I just removed the line and kept the patch as it is to keep the credits for who made this update and also I tested it and it worked with no problem.
Description
implements wlr-tablet-v2 for drawing tablets and supports cursor emulation
inspired by @guyuming76's branch, with coding help from @Palanix and testing by @Thanatos
Please note: wlroots modified the order of arguments to the function wlr_surface_accepts_tablet_v2
In versions less than or equal to 0.18.1 (against which, dwl 0.7 is typically built), the order is tablet, surface.
In the master branch and (anticipated) in versions later than 0.18.1, the order is surface, tablet.
The git branch for this patch uses the surface, tablet order.
If you are attempting to use this codebase to make your own modifications to the patch, there is only one call to the wlr_surface_accepts_tablet_v2 function, but you will need to make the argument order change if you expect to build against wlroots 0.18.1 or earlier.
The 0.7 patch linked here accounts for the change and uses the tablet, surface order, but the patch is orphaned from a codebase.
There was discussion of this matter in Issue #141.