Remove tor_gettimeofday_cached_monotonic as broken and unneeded

src/common/compat_libevent.c

@@ -388,33 +388,3 @@ tor_gettimeofday_cache_set(const struct timeval *tv)
 #endif
 #endif
 
-/**
- * As tor_gettimeofday_cached, but can never move backwards in time.
- *
- * The returned value may diverge from wall-clock time, since wall-clock time
- * can trivially be adjusted backwards, and this can't.  Don't mix wall-clock
- * time with these values in the same calculation.
- *
- * Depending on implementation, this function may or may not "smooth out" huge
- * jumps forward in wall-clock time.  It may or may not keep its results
- * advancing forward (as opposed to stalling) if the wall-clock time goes
- * backwards.  The current implementation does neither of of these.
- *
- * This function is not thread-safe; do not call it outside the main thread.
- *
- * In future versions of Tor, this may return a time does not have its
- * origin at the Unix epoch.
- */
-void
-tor_gettimeofday_cached_monotonic(struct timeval *tv)
-{
-  struct timeval last_tv = { 0, 0 };
-
-  tor_gettimeofday_cached(tv);
-  if (timercmp(tv, &last_tv, OP_LT)) {
-    memcpy(tv, &last_tv, sizeof(struct timeval));
-  } else {
-    memcpy(&last_tv, tv, sizeof(struct timeval));
-  }
-}
-

src/common/compat_libevent.h

@@ -70,7 +70,6 @@ void tor_gettimeofday_cache_clear(void);
 #ifdef TOR_UNIT_TESTS
 void tor_gettimeofday_cache_set(const struct timeval *tv);
 #endif
-void tor_gettimeofday_cached_monotonic(struct timeval *tv);
 
 #ifdef COMPAT_LIBEVENT_PRIVATE