Remove LocalInternedString::get.

It has a single use, which is easily changed to something better.

src/librustc_mir/borrow_check/error_reporting.rs

@@ -336,7 +336,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let local = &self.body.local_decls[local_index];
         match local.name {
             Some(name) if !local.from_compiler_desugaring() => {
-                buf.push_str(name.as_str().get());
+                buf.push_str(&name.as_str());
                 Ok(())
             }
             _ => Err(()),

src/libsyntax_pos/symbol.rs

@@ -1168,15 +1168,6 @@ impl LocalInternedString {
             string: unsafe { std::mem::transmute::<&str, &str>(string) }
         }
     }
-
-    #[inline]
-    pub fn get(&self) -> &str {
-        // This returns a valid string since we ensure that `self` outlives the interner
-        // by creating the interner on a thread which outlives threads which can access it.
-        // This type cannot move to a thread which outlives the interner since it does
-        // not implement Send.
-        self.string
-    }
 }
 
 impl<U: ?Sized> std::convert::AsRef<U> for LocalInternedString