[FR] Option for mobile-install command to install to all connected devices

[veniversum]

This is a feature request to support the use case of running mobile-install on multiple connected devices. Currently mobile-install needs to be invoked multiple times with --adb_arg=-s --adb_arg=<SERIAL> for each ADB connected device.

Buck's install command has a multi-install mode which enumerates connected devices and installs to all of them, a similar option would be helpful in Bazel.

-all (-x) Install APK on all connected devices and/or emulators (multi-install mode).