std: convert {vec,str}::to_owned to methods.

src/libsyntax/ext/log_syntax.rs

@@ -28,7 +28,7 @@ pub fn expand_syntax_ext(cx: @ExtCtxt,
     cx.print_backtrace();
     io::stdout().write_line(
         print::pprust::tt_to_str(
-            ast::tt_delim(vec::to_owned(tt)),
+            ast::tt_delim(tt.to_owned()),
             get_ident_interner()));
 
     //trivial expression