Update prebuilt Clang to r349610b.

clang 8.0.9 (based on r349610b) from build 5331180.

Bug: http://b/122481018
Test: N/A
Change-Id: I6960ead142a31e496aec64a9e6d8e18113aaaed5
(cherry picked from commit 3885f0063d5d67adece7ab0b2f74de17cc0ae1e4)
2129 files changed