servo: Merge #17080 - Update rustc (from jdm:updaterust); r=nox

This brings in rust-lang/rust#39160 which significantly improves the default debugging experience on macOS.

Source-Repo: https://github.com/servo/servo
Source-Revision: ad4a5411a9620cee5cd93d5fe1a3dbad02cc0812

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 0c1abc4ad87968a2ebcd0a2f9d80612f0c58cc78

servo/components/profile/mem.rs

@@ -505,11 +505,6 @@ mod system_reporter {
         None
     }
 
-    // Like std::macros::try!, but for Option<>.
-    macro_rules! option_try(
-        ($e:expr) => (match $e { Some(e) => e, None => return None })
-    );
-
     #[cfg(target_os = "linux")]
     fn page_size() -> usize {
         unsafe {
@@ -522,6 +517,11 @@ mod system_reporter {
         use std::fs::File;
         use std::io::Read;
 
+        // Like std::macros::try!, but for Option<>.
+        macro_rules! option_try(
+            ($e:expr) => (match $e { Some(e) => e, None => return None })
+        );
+
         let mut f = option_try!(File::open("/proc/self/statm").ok());
         let mut contents = String::new();
         option_try!(f.read_to_string(&mut contents).ok());

servo/rust-commit-hash

@@ -1 +1 @@
-e17a1227ac779a181b2839998e26a7e4e434c2a0
+03bed655142dd5e42ba4539de53b3663d8a123e0