Merge ref 'e8e4541ff196' from rust-lang/rust

Pull recent changes from https://github.com/rust-lang/rust via Josh.

Upstream ref: rust-lang/rust@e8e4541
Filtered ref: 77fb39b
Upstream diff: rust-lang/rust@4c42051...e8e4541

This merge was created using https://github.com/rust-lang/josh-sync.

Author: The rustc-josh-sync Cronjob Bot

crates/proc-macro-srv/src/dylib/proc_macros.rs

@@ -7,7 +7,7 @@ pub(crate) struct ProcMacros([bridge::client::ProcMacro]);
 
 impl From<bridge::PanicMessage> for crate::PanicMessage {
     fn from(p: bridge::PanicMessage) -> Self {
-        Self { message: p.as_str().map(|s| s.to_owned()) }
+        Self { message: p.into_string() }
     }
 }