[PATCH maint-1.7.6] fast-import: leakfix for 'ls' of dirty trees

When the chosen directory has changed since it was last written to
pack, "tree_content_get" makes a deep copy of its content to scribble
on while computing the tree name, which we forgot to free.

This leak has been present since the 'ls' command was introduced in
v1.7.5-rc0~3^2~33 (fast-import: add 'ls' command, 2010-12-02).

Signed-off-by: Jonathan Nieder <redacted>
---
Sorry to have missed this buglet for so long.  (Doubly so because it
was noticed and commented on half a year ago before being promptly
forgotten.)  Patch is against commit 8dc6a373d2 which introduced the
leaky 'ls' support.

 fast-import.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/fast-import.c b/fast-import.c
index 6c37b840..fff285cd 100644
--- a/fast-import.c
+++ b/fast-import.c

@@ -2987,6 +2987,8 @@ static void parse_ls(struct branch *b)
 		store_tree(&leaf);
 
 	print_ls(leaf.versions[1].mode, leaf.versions[1].sha1, p);
+	if (leaf.tree)
+		release_tree_content_recursive(leaf.tree);
 	if (!b || root != &b->branch_tree)
 		release_tree_entry(root);
 }

-- 
1.7.9.2