Merge branch 'ds/line-log-on-bloom'

"git log -L..." now takes advantage of the "which paths are touched
by this commit?" info stored in the commit-graph system.

* ds/line-log-on-bloom:
  line-log: integrate with changed-path Bloom filters
  line-log: try to use generation number-based topo-ordering
  line-log: more responsive, incremental 'git log -L'
  t4211-line-log: add tests for parent oids
  line-log: remove unused fields from 'struct line_log_data'

bloom.c

@@ -138,6 +138,11 @@ void fill_bloom_key(const char *data,
 		key->hashes[i] = hash0 + i * hash1;
 }
 
+void clear_bloom_key(struct bloom_key *key)
+{
+	FREE_AND_NULL(key->hashes);
+}
+
 void add_key_to_filter(const struct bloom_key *key,
 		       struct bloom_filter *filter,
 		       const struct bloom_filter_settings *settings)