Make '--decorate' set an explicit 'show_decorations' flag

We will want to add decorations without necessarily showing them, so add
an explicit revisions info flag as to whether we're showing decorations
or not.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin-log.c b/builtin-log.c
index 176cbce..82ea07b 100644
--- a/builtin-log.c
+++ b/builtin-log.c
@@ -28,7 +28,6 @@
 		      struct rev_info *rev)
 {
 	int i;
-	int decorate = 0;
 
 	rev->abbrev = DEFAULT_ABBREV;
 	rev->commit_format = CMIT_FMT_DEFAULT;
@@ -55,7 +54,7 @@
 		const char *arg = argv[i];
 		if (!strcmp(arg, "--decorate")) {
 			load_ref_decorations();
-			decorate = 1;
+			rev->show_decorations = 1;
 		} else if (!strcmp(arg, "--source")) {
 			rev->show_source = 1;
 		} else
diff --git a/log-tree.c b/log-tree.c
index cf7947b..5444f08 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -59,6 +59,8 @@
 
 	if (opt->show_source && commit->util)
 		printf(" %s", (char *) commit->util);
+	if (!opt->show_decorations)
+		return;
 	decoration = lookup_decoration(&name_decoration, &commit->object);
 	if (!decoration)
 		return;
diff --git a/revision.h b/revision.h
index 51a4863..0a1806a 100644
--- a/revision.h
+++ b/revision.h
@@ -54,6 +54,7 @@
 			rewrite_parents:1,
 			print_parents:1,
 			show_source:1,
+			show_decorations:1,
 			reverse:1,
 			reverse_output_stage:1,
 			cherry_pick:1,