Add // run-pass annotations to all the tests under ui/run-pass/.

(I may have accidentally added it to some auxilliary crates as well;
my emacs-macro-based methodology was pretty crude.)

src/test/ui/run-pass/array-slice-vec/array_const_index-1.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// run-pass
+
 #![feature(const_indexing)]
 
 fn main() {