Merge branch 'ds/more-index-cleanups'

Cleaning various codepaths up.

* ds/more-index-cleanups:
  t1092: test interesting sparse-checkout scenarios
  test-lib: test_region looks for trace2 regions
  sparse-checkout: load sparse-checkout patterns
  name-hash: use trace2 regions for init
  repository: add repo reference to index_state
  fsmonitor: de-duplicate BUG()s around dirty bits
  cache-tree: extract subtree_pos()
  cache-tree: simplify verify_cache() prototype
  cache-tree: clean up cache_tree_update()

cache.h

@@ -328,6 +328,7 @@ struct index_state {
 	struct ewah_bitmap *fsmonitor_dirty;
 	struct mem_pool *ce_mem_pool;
 	struct progress *progress;
+	struct repository *repo;
 };
 
 /* Name hashing */