create_legacy_bootloader_templates: re-enable chromeos-vusb with --enable-rootfs_verification

create_legacy_bootloader_templates.sh

Index: create_legacy_bootloader_templates.sh
diff --git a/create_legacy_bootloader_templates.sh b/create_legacy_bootloader_templates.sh
index 36adbb767096e856aeb23266946f830a4460d4c7..9cfd48f8fd14d62fe4be21061100d2fcd0b0e7fe 100755
--- a/create_legacy_bootloader_templates.sh
+++ b/create_legacy_bootloader_templates.sh
@@ -99,13 +99,16 @@ EOF
   info "Emitted ${SYSLINUX_DIR}/syslinux.cfg"
 
   if [[ ${FLAGS_enable_rootfs_verification} -eq ${FLAGS_TRUE} ]]; then
-    # TODO(wad, tgao) enable usb vbooting with initramfs or device probing.
-    warn "USB booting will not use rootfs verification."
-  fi
-  # To change the active target, only this file needs to change.
-  cat <<EOF | sudo dd of="${SYSLINUX_DIR}/default.cfg" 2>/dev/null
+    # To change the active target, only this file needs to change.
+    cat <<EOF | sudo dd of="${SYSLINUX_DIR}/default.cfg" 2>/dev/null
+DEFAULT chromeos-vusb.A
+EOF
+  else
+    # To change the active target, only this file needs to change.
+    cat <<EOF | sudo dd of="${SYSLINUX_DIR}/default.cfg" 2>/dev/null
 DEFAULT chromeos-usb.A
 EOF
+  fi
   info "Emitted ${SYSLINUX_DIR}/default.cfg"
 
   cat <<EOF | sudo dd of="${SYSLINUX_DIR}/usb.A.cfg" 2>/dev/null