[automerger skipped] Remove include of backtrace/Backtrace.h.
am: 98877cbabe -s ours
am skip reason: change_id I85c2837c5a539ccefc5a7140949988058d21697a with SHA1 3336c7bce0 is in history

Change-Id: Icdeac41045ae4890b925d999d85a6a219f5b9000