Clean up temporary files and directories left by build_image, etc.

src/scripts/mod_image_for_test.sh

Index: src/scripts/mod_image_for_test.sh
diff --git a/src/scripts/mod_image_for_test.sh b/src/scripts/mod_image_for_test.sh
index c38fc92117342153e6e099b380fc304177b735ee..8d778e9d2f636018e39b15588eaf34faf0c19e82 100755
--- a/src/scripts/mod_image_for_test.sh
+++ b/src/scripts/mod_image_for_test.sh
@@ -75,6 +75,8 @@ cleanup() {
     cleanup_rootfs_loop
   fi
 
+  rmdir "${ROOT_FS_DIR}"
+
   # Turn die on error back on.
   set -e
 }
@@ -94,11 +96,12 @@ else
 fi
 
 set -e
-trap cleanup EXIT
 
 ROOT_FS_DIR=$(dirname "${FLAGS_image}")/rootfs
 mkdir -p "${ROOT_FS_DIR}"
 
+trap cleanup EXIT
+
 # Figure out how to loop mount the rootfs partition. It should be partition 3
 # on the disk image.
 offset=$(partoffset "${FLAGS_image}" 3)