use channel_is_client for create cell counts

When a relay is collecting internal statistics about how many
create cell requests it has seen of each type, accurately count the
requests from relays that temporarily fall out of the consensus.

(To be extra conservative, we were already ignoring requests from clients
in our counts, and we continue ignoring them here.)

Fixes bug 24910; bugfix on 0.2.4.17-rc.

changes/bug24910

@@ -0,0 +1,7 @@
+  o Minor bugfixes (relay statistics):
+    - When a relay is collecting internal statistics about how many
+      create cell requests it has seen of each type, accurately count the
+      requests from relays that temporarily fall out of the consensus. (To
+      be extra conservative, we were already ignoring requests from
+      clients in our counts, and we continue ignoring them here.) Fixes
+      bug 24910; bugfix on 0.2.4.17-rc.

src/or/command.c

@@ -339,7 +339,9 @@ command_process_create_cell(cell_t *cell, channel_t *chan)
     return;
   }
 
-  if (connection_or_digest_is_known_relay(chan->identity_digest)) {
+  if (!channel_is_client(chan)) {
+    /* remember create types we've seen, but don't remember them from
+     * clients, to be extra conservative about client statistics. */
     rep_hist_note_circuit_handshake_requested(create_cell->handshake_type);
   }
 

src/or/cpuworker.c

@@ -547,7 +547,7 @@ assign_onionskin_to_cpuworker(or_circuit_t *circ,
     return 0;
   }
 
-  if (connection_or_digest_is_known_relay(circ->p_chan->identity_digest))
+  if (!channel_is_client(circ->p_chan))
     rep_hist_note_circuit_handshake_assigned(onionskin->handshake_type);
 
   should_time = should_time_request(onionskin->handshake_type);