Fix ui-fulldeps test

Author: estebank

src/test/ui-fulldeps/gated-plugin.stderr

@@ -1,9 +1,10 @@
-error[E0658]: compiler plugins are experimental and possibly buggy (see issue #29597)
+error[E0658]: compiler plugins are experimental and possibly buggy
   --> $DIR/gated-plugin.rs:3:1
    |
 LL | #![plugin(attr_plugin_test)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/29597
    = help: add #![feature(plugin)] to the crate attributes to enable
 
 error: aborting due to previous error

src/test/ui-fulldeps/hash-stable-is-unstable.stderr

@@ -2,44 +2,49 @@ error[E0601]: `main` function not found in crate `hash_stable_is_unstable`
    |
    = note: consider adding a `main` function to `$DIR/hash-stable-is-unstable.rs`
 
-error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
+error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:3:1
    |
 LL | extern crate rustc_data_structures;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/27812
    = help: add #![feature(rustc_private)] to the crate attributes to enable
 
-error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
+error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:5:1
    |
 LL | extern crate rustc;
    | ^^^^^^^^^^^^^^^^^^^
    |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/27812
    = help: add #![feature(rustc_private)] to the crate attributes to enable
 
-error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
+error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:7:1
    |
 LL | extern crate rustc_macros;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/27812
    = help: add #![feature(rustc_private)] to the crate attributes to enable
 
-error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
+error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:10:5
    |
 LL | use rustc_macros::HashStable;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
    |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/27812
    = help: add #![feature(rustc_private)] to the crate attributes to enable
 
-error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
+error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
   --> $DIR/hash-stable-is-unstable.rs:13:10
    |
 LL | #[derive(HashStable)]
    |          ^^^^^^^^^^
    |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/27812
    = help: add #![feature(rustc_private)] to the crate attributes to enable
 
 error: aborting due to 6 previous errors