Merge #1253

1253: Share literal validation logic with compiler r=matklad a=matklad

This is neat: the unescape module is literary what compiler is using right now:

https://github.com/rust-lang/rust/blob/c6ac57564852cb6e2d0db60f7b46d9eb98d4b449/src/libsyntax/parse/unescape.rs

So, yeah, code sharing via copy-paste!



Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>

Author: bors[bot]

crates/ra_syntax/src/lib.rs

@@ -23,7 +23,6 @@ mod syntax_node;
 mod syntax_text;
 mod syntax_error;
 mod parsing;
-mod string_lexing;
 mod validation;
 mod ptr;