This takes down LLVM IR size of theme_selector from 316k to ~250k. Note
that I do not care about theme_selector in particular, though it acts as
a benchmark for smaller crates to me ("how much static overhead in
compile time does gpui have").
The title is a bit dramatic, so just to shed some light: by leaking a
type I mean forcing downstream crates to codegen it's methods/know about
it's drop code. Since SubscriberSet is no longer used directly in the
generic (==inlineable) methods, users no longer have to codegen `insert`
and co.
Release Notes:
- N/A
Piotr Osiewicz
1446fb7632