Refactor stderr_prints_nothing into a more modular function

src/libstd/sys_common/util.rs

@@ -10,14 +10,13 @@
 
 use fmt;
 use io::prelude::*;
-use sys::stdio::{Stderr, stderr_prints_nothing};
+use sys::stdio::panic_output;
 use thread;
 
 pub fn dumb_print(args: fmt::Arguments) {
-    if stderr_prints_nothing() {
-        return
+    if let Some(mut out) = panic_output() {
+        let _ = out.write_fmt(args);
     }
-    let _ = Stderr::new().map(|mut stderr| stderr.write_fmt(args));
 }
 
 // Other platforms should use the appropriate platform-specific mechanism for