Clang upload_revision.py, add TODO about bug number

To make it harder to forget.

Bug: none
Change-Id: Iecf97569c56383ade299f264ae0946738e91b60b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2214884
Auto-Submit: Hans Wennborg <hans@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#771580}

tools/clang/scripts/upload_revision.py

@@ -29,6 +29,7 @@ CHROMIUM_DIR = os.path.abspath(os.path.join(THIS_DIR, '..', '..', '..'))
 # Keep lines in here at <= 72 columns, else they wrap in gerrit.
 COMMIT_FOOTER = \
 '''
+TODO: Add bug number.
 
 Cq-Include-Trybots: chromium/try:mac_chromium_asan_rel_ng
 Cq-Include-Trybots: chromium/try:linux_chromium_cfi_rel_ng