Import platform SDK from build 7121503

./update_prebuilts.py -p 7121503

Bug: 177266501
Merged-In: I5783cdfb560fcd6462217cd5787a86a046dcc600
Change-Id: I5783cdfb560fcd6462217cd5787a86a046dcc600
(cherry picked from commit d08799b94640cc221074a3bbb2ca010f8336da20)
39 files changed