Merge "fastbootd: Fix transport ownership."

fastboot/engine.cpp

fastboot/fastboot.cpp

fastboot/fastboot_driver.cpp

fastboot/fastboot_driver.h

fastboot/fuzzy_fastboot/fixtures.cpp

fastboot/fuzzy_fastboot/usb_transport_sniffer.cpp

fastboot/fuzzy_fastboot/usb_transport_sniffer.h

fastboot/usb_linux.cpp

fastboot/usb_osx.cpp

fastboot/usb_windows.cpp