Add notice of requesting source code in scheduling

Flag: EXEMPT license change for b/418865751
Bug: 418865751
Test: presubmits
Test: lunch husky-trunk_staging-eng && m, an extra line is added at the top of NOTICE.html file in NOTICE.html.gz
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:aede8e953fbb556686c6fa12df805e7cd6821edb)
Merged-In: I88304320c4ede6af8b2961e82e8e13b93349d68e
Change-Id: I88304320c4ede6af8b2961e82e8e13b93349d68e