Export core::str::from_raw_parts{,_mut} into alloc::str and std::str

Author: dtolnay

Diff for: library/alloc/src/str.rs

@@ -30,6 +30,8 @@ pub use core::str::SplitAsciiWhitespace;
 pub use core::str::SplitInclusive;
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::str::SplitWhitespace;
+#[unstable(feature = "str_from_raw_parts", issue = "119206")]
+pub use core::str::{from_raw_parts, from_raw_parts_mut};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::str::{from_utf8, from_utf8_mut, Bytes, CharIndices, Chars};
 #[stable(feature = "rust1", since = "1.0.0")]