Merge branch 'sb/more-repo-in-api'

The in-core repository instances are passed through more codepaths.

* sb/more-repo-in-api: (23 commits)
  t/helper/test-repository: celebrate independence from the_repository
  path.h: make REPO_GIT_PATH_FUNC repository agnostic
  commit: prepare free_commit_buffer and release_commit_memory for any repo
  commit-graph: convert remaining functions to handle any repo
  submodule: don't add submodule as odb for push
  submodule: use submodule repos for object lookup
  pretty: prepare format_commit_message to handle arbitrary repositories
  commit: prepare logmsg_reencode to handle arbitrary repositories
  commit: prepare repo_unuse_commit_buffer to handle any repo
  commit: prepare get_commit_buffer to handle any repo
  commit-reach: prepare in_merge_bases[_many] to handle any repo
  commit-reach: prepare get_merge_bases to handle any repo
  commit-reach.c: allow get_merge_bases_many_0 to handle any repo
  commit-reach.c: allow remove_redundant to handle any repo
  commit-reach.c: allow merge_bases_many to handle any repo
  commit-reach.c: allow paint_down_to_common to handle any repo
  commit: allow parse_commit* to handle any repo
  object: parse_object to honor its repository argument
  object-store: prepare has_{sha1, object}_file to handle any repo
  object-store: prepare read_object_file to deal with any repo
  ...

pretty.h

@@ -104,9 +104,14 @@ void pp_remainder(struct pretty_print_context *pp, const char **msg_p,
  * Put the result to "sb".
  * Please use this function for custom formats.
  */
-void format_commit_message(const struct commit *commit,
+void repo_format_commit_message(struct repository *r,
+			const struct commit *commit,
 			const char *format, struct strbuf *sb,
 			const struct pretty_print_context *context);
+#ifndef NO_THE_REPOSITORY_COMPATIBILITY_MACROS
+#define format_commit_message(c, f, s, con) \
+	repo_format_commit_message(the_repository, c, f, s, con)
+#endif
 
 /*
  * Parse given arguments from "arg", check it for correctness and