Support starting remote GCE with multiple devices inside the VM.

Bug: 146643038
Test: acloud-dev create_cf --branch git_master --build_target
cf_x86_phone-userdebug --num-avds-per-instance 2

Change-Id: I17f57a812c7903b1e63d1634494b1df9c6e9534d
2 files changed