rustc_log: remove direct dep on tracing_core

required features reexported from tracing

Author: klensy

Cargo.lock

@@ -4072,7 +4072,6 @@ name = "rustc_log"
 version = "0.0.0"
 dependencies = [
  "tracing",
- "tracing-core",
  "tracing-subscriber",
  "tracing-tree",
 ]

compiler/rustc_log/src/lib.rs

@@ -38,7 +38,7 @@ use std::fmt::{self, Display};
 use std::io::{self, IsTerminal};
 
 use tracing::dispatcher::SetGlobalDefaultError;
-use tracing_core::{Event, Subscriber};
+use tracing::{Event, Subscriber};
 use tracing_subscriber::filter::{Directive, EnvFilter, LevelFilter};
 use tracing_subscriber::fmt::FmtContext;
 use tracing_subscriber::fmt::format::{self, FormatEvent, FormatFields};