Fix @code escapes

The body of {@code} must not be HTML escaped. This is one of
several changes that fix the source in conjunction with a
doclava fix.

Bug: 25757239
(cherry-picked from commit f9786c79082e3e5956238262cebf8c6bb69f1e42)
Change-Id: Iafb0959a02f8b7f80e536a08f5e9c30862af0c27
2 files changed