[jit][edge] Implement torch::jit::Function for mobile funciton. (#65970)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/65970
ghstack-source-id: 141842338
mobile::Function should inherit from jit::Function, because for interface call support, we need an abstract jit::Function type stored in corresponding ClassTypes, so that we can look up methods in there. Previously mobile::Function is implemented separately which prevents this. Since we get rid of all the unneeded virtual methods from jit::Function, we can inherit from torch::jit::Function without too much cost.
NOTE that torch::jit::Function is already in dependency because we need it to support custom class call. We should be able to use Function uniformly without looking into whether it's a builtin function or mobile::Function.
Test Plan: no behavior change.
Reviewed By: iseeyuan, mrshenli
Differential Revision: D31326148
fbshipit-source-id: 36caeaf3c8c5f54c23a1a7c8c9e2fd6e78b19622
