Run Fuchsia development commands. Must be run from a directory
that is contained in a Platform Source Tree.

fx help flags: fx help [OPTION]
  --no-contrib      Hide contrib commands (see //tools/devshell/README.md)
  --deprecated      Do not hide deprecated commands

Global fx options: fx [OPTION]  ...
  --dir=BUILD_DIR           Path to the build directory to use when running COMMAND.
  -d=DEVICE[:SSH_PORT]      Target a specific device.
                            DEVICE may be a Fuchsia device name to be resolved using
                            ffx or an IP address.
                            An IPv4 address must be specified directly, while an IPv6
                            need to be surrounded by brackets.
                            SSH_PORT, if specified, will be used for all commands
                            that rely on SSH to connect to the device instead of the
                            default SSH port (22).
                            Note: See "fx help set-device" for more help and to set
                            the default device for a BUILD_DIR.
  -i                        Iterative mode.  Repeat the command whenever a file is
                            modified under your Fuchsia directory, not including
                            out/.
  -x                        Print commands and their arguments as they are executed.
  -xx                       Print extra logging of the fx tool itself (implies -x)
  --enable|disable=FEATURE  Enable or disable a feature (non-persistent). Valid features:
      fxtest_auto_publishes_packages
            (default=enabled, current=enabled)
            Enables 'fx test' to automatically publish packages to the package
            repository server.
      incremental
            (default=enabled, current=enabled)
            Packages are published and served incrementally by 'fx serve'
            as they are built. Explicit 'fx build' is not required for most operations.
      incremental_legacy
            (default=disabled, current=disabled)
            Packages are published and served incrementally by 'fx serve'
            as they are built using the legacy incremental publisher. Explicit
            'fx build' is not required for most operations.
      incremental_new
            (default=disabled, current=disabled)
            Packages are published and served incrementally by 'fx serve'
            as they are built. Explicit 'fx build' is not required for most operations.
      legacy_fastboot
            (default=disabled, current=disabled)
            Device provisioning based on legacy fastboot instead of ffx.
      legacy_fxtest
            (default=disabled, current=disabled)
            Use the old Dart implementation of fx test rather than the new Python one.