If a _guessed_ compression method fails, it is never PROTOCOL_WARN.

Rationale: When use a guessed compression method, we already gave a
PROTOCOL_WARN when our guess differed from the declared method,
AND we gave a PROTOCOL_WARN when the declared method failed.  It is
not a protocol problem that the guessed method failed too; it's just
a recovery attempt that failed.

changes/bug22670

@@ -0,0 +1,4 @@
+  o Minor bugfixes (logging, compression):
+    - When decompressing, do not warn if we fail to decompress using a
+      compression method that we merely guessed. Fixes part of
+      bug 22670; bugfix on 0.1.1.14-alpha.

src/or/directory.c

@@ -2271,7 +2271,7 @@ dir_client_decompress_response_body(char **bodyp, size_t *bodylenp,
   if (!new_body && tor_compress_supports_method(guessed) &&
       compression != guessed) {
     tor_uncompress(&new_body, &new_len, body, body_len, guessed,
-                   !allow_partial, LOG_PROTOCOL_WARN);
+                   !allow_partial, LOG_INFO);
     tried_both = 1;
   }
   /* If we're pretty sure that we have a compressed directory, and