gpui: Sweep through cargo doc output and mark dubious items as non-public (#3932)

I essentially went through the publicly exported items and marked these
that are e.g. leaky reexports as pub(crate). I expect that'd be done on
Tuesday anyways.

Release Notes:
- N/A

crates/gpui/src/platform/mac/platform.rs

@@ -56,9 +56,6 @@ use time::UtcOffset;
 #[allow(non_upper_case_globals)]
 const NSUTF8StringEncoding: NSUInteger = 4;
 
-#[allow(non_upper_case_globals)]
-pub const NSViewLayerContentsRedrawDuringViewResize: NSInteger = 2;
-
 const MAC_PLATFORM_IVAR: &str = "platform";
 static mut APP_CLASS: *const Class = ptr::null();
 static mut APP_DELEGATE_CLASS: *const Class = ptr::null();
@@ -404,7 +401,7 @@ impl Platform for MacPlatform {
         // this, we make quitting the application asynchronous so that we aren't holding borrows to
         // the app state on the stack when we actually terminate the app.
 
-        use super::dispatcher::{dispatch_async_f, dispatch_get_main_queue};
+        use super::dispatcher::{dispatch_get_main_queue, dispatch_sys::dispatch_async_f};
 
         unsafe {
             dispatch_async_f(dispatch_get_main_queue(), ptr::null_mut(), Some(quit));