Upgrade emulator to emu-master-dev build 3840836
am: d3988c7d54

Change-Id: I538faafd50867d5d7961be699fa1d0f55ef9d390
tree: 4ad27ccf376efa74442353a2a4e64b66a73e4bb3
  1. darwin-x86_64/
  2. linux-x86_64/
  3. .gitignore
  4. NOTICE
  5. README
  6. update_emulator.sh