Merge changes from topic "fastboot_fetch"
* changes:
fuzzy_fastboot: Add tests for fetch:vendor_boot
fuzzy_fastboot: Add conformance test for getvar:max-fetch-size.
fastboot driver: repack vendor boot ramdisk
fastboot driver: Allow colon in partition name when flashing
fastboot driver: add fetch command in driver
fastboot driver: RunAndReadBuffer don't allocate too much mem
fastboot driver: add RunAndReadBuffer helper
fastboot driver: Fix ownership of fd in fastboot_buffer.
fastboot driver: fix message
fastbootd: add O_CLOEXEC/O_BINARY for OpenPartition
fastbootd: add read arg to OpenPartition
fastbootd: Add fetch command on device
fastbootd: Add getvar max-fetch-size.