matroskamux: Fix various memory leaks in the unit test

https://bugzilla.gnome.org/show_bug.cgi?id=790686
diff --git a/tests/check/elements/matroskamux.c b/tests/check/elements/matroskamux.c
index 23e56d9..8f3a053 100644
--- a/tests/check/elements/matroskamux.c
+++ b/tests/check/elements/matroskamux.c
@@ -347,6 +347,8 @@
   compare_buffer_to_data (outbuffer, data_h1, sizeof (data_h1));
   gst_buffer_unref (outbuffer);
   gst_buffer_unref (gst_harness_pull (h));
+
+  gst_harness_teardown (h);
 }
 
 GST_END_TEST;
@@ -592,6 +594,7 @@
     if (gst_tag_list_get_tag_size (tags, GST_TAG_TITLE) > 0) {
       gst_tag_list_get_string_index (tags, GST_TAG_TITLE, 0, &title);
       fail_unless (memcmp (info->data + *index, title, strlen (title)) == 0);
+      g_free (title);
     }
     *index += len;
 
@@ -743,6 +746,7 @@
   fail_unless (gst_tag_list_get_tag_size (tags, tag_type) > 0);
   gst_tag_list_get_string_index (tags, tag_type, 0, &cur_tag_string);
   fail_unless (g_strcmp0 (cur_tag_string, tag_string) == 0);
+  g_free (cur_tag_string);
 }
 
 static void
@@ -970,6 +974,7 @@
   gst_toc_unref (ref_toc);
 
   gst_buffer_unmap (merged_buffer, &info);
+  gst_buffer_unref (merged_buffer);
   gst_harness_teardown (h);
 }