Second stage of rust-lang#43067

The previous code would parse the TestProps, and then parse them
again with a revision set, adding some elements (like aux_builds)
a second time to the existing TestProps.

* Re-run rustdoc tests if rustdoc or htmldocck.py was updated.
* Put stamp files in the correct subdirectories to avoid clashes when
the file names match but the subdirectory doesn't.

The `ErrorId` variant takes a u16 so that `DiagnosticMessageId` can retain
its `Copy` status (the present author's first choice having been the "EXXX"
code as a string).

The duplicated "type mismatch resolving `{}`" literal is unfortunate, but
the `struct_span_err!` macro (which we want to mark that error code as
used) is fussy about taking a literal, and the one-time-diagnostics set
needs an owned string.

This is concerning rust-lang#33941 and probably rust-lang#45805!

Remove deprecated message

Follow up of rust-lang#43067

…chton

Redox: Return true from Path::is_absolute if a Path contains root or a scheme

In Redox, different subsystems have different filesystem paths. However, the majority of applications using the `Path::is_absolute` function really only want to know if a path is absolute from the perspective of the scheme it is currently running in, usually `file:`. This makes both `file:/` and `/` return `true` from `Path::is_absolute`, meaning that most code does not have to check if it is running on Redox.

Code that wants to know if a path contains a scheme can implement such a check on its own.

Related to rust-lang#45893

Redox: Use futex timeout to implement CondVar::wait_timeout

`CondVar::wait_timeout` is implemented by supplying a `TimeSpec` pointer to `futex`. In addition, all calls to `unimplemented!()` have been removed from the Redox `sys` module.

Related to rust-lang#45892

…rsing, r=alexcrichton

Fix test case header parsing code in presence of multiple revisions.

The previous code would parse the TestProps, and then parse them again with a revision set, adding some elements (like aux_builds) a second time to the existing TestProps.

…ichton

compiletest: Fix a couple of test re-run issues

* Re-run rustdoc tests if rustdoc or htmldocck.py was updated.
* Put stamp files in the correct subdirectories to avoid clashes when
the file names match but the subdirectory doesn't.

…bank

MIR-borrowck: fix diagnostics for closures

Emit notes for captured variables in the same manner as AST borrowck.

```
error[E0499]: cannot borrow `x` as mutable more than once at a time (Ast)
  --> $DIR/borrowck-closures-two-mut.rs:24:24
   |
23 |     let c1 = to_fn_mut(|| x = 4);
   |                        -- - previous borrow occurs due to use of `x` in closure
   |                        |
   |                        first mutable borrow occurs here
24 |     let c2 = to_fn_mut(|| x = 5); //~ ERROR cannot borrow `x` as mutable more than once
   |                        ^^ - borrow occurs due to use of `x` in closure
   |                        |
   |                        second mutable borrow occurs here
25 | }
   | - first borrow ends here

error[E0499]: cannot borrow `x` as mutable more than once at a time (Mir)
  --> $DIR/borrowck-closures-two-mut.rs:24:24
   |
23 |     let c1 = to_fn_mut(|| x = 4);
   |                        -- - previous borrow occurs due to use of `x` in closure
   |                        |
   |                        first mutable borrow occurs here
24 |     let c2 = to_fn_mut(|| x = 5); //~ ERROR cannot borrow `x` as mutable more than once
   |                        ^^ - borrow occurs due to use of `x` in closure
   |                        |
   |                        second mutable borrow occurs here
25 | }
   | - first borrow ends here
```

Fixes rust-lang#45362.

…crichton

Refactor Option::filter method

…stebank

deduplicate projection error (E0271) messages

The `ErrorId` variant takes a u16 so that `DiagnosticMessageId` can retain
its `Copy` status (the present author's first choice having been the "EXXX"
code as a string).

The duplicated "type mismatch resolving `{}`" literal is unfortunate, but
the `struct_span_err!` macro (which we want to mark that error code as
used) is fussy about taking a literal, and the one-time-diagnostics set
needs an owned string.

This is concerning rust-lang#33941 and probably rust-lang#45805!

r? @estebank

Fix style in interner test