Rollup merge of #26464 - Gankro:send, r=alexcrichton

Vec contains `Unique<T>` and some usizes, this is already derived.

src/libcollections/vec.rs

@@ -157,9 +157,6 @@ pub struct Vec<T> {
     cap: usize,
 }
 
-unsafe impl<T: Send> Send for Vec<T> { }
-unsafe impl<T: Sync> Sync for Vec<T> { }
-
 ////////////////////////////////////////////////////////////////////////////////
 // Inherent methods
 ////////////////////////////////////////////////////////////////////////////////

src/test/compile-fail/coherence-orphan.rs

@@ -27,6 +27,5 @@ impl TheTrait<isize> for TheType { }
 
 impl !Send for Vec<isize> { }
 //~^ ERROR E0117
-//~| ERROR E0119
 
 fn main() { }