[Q] Random code in recovery mode topic

When I boot into recovery mode on my One, I get this text at the bottom of the screen:

E:missing bitmap oem_unlock_bg
(Code -1)
E:missing bitmap oem_unlock_bg_yes
(Code -1)
E:missing bitmap oem_unlock_bg_no
(Code -1)
E:missing bitmap icon_ruu
(Code -1)
Write host_mode success
handle_cota_install: Can't mount /sdcard, 1 times
handle_cota_install: Can't mount /sdcard, 2 times
handle_cota_install: Can't mount /sdcard, 3 times
handle_cota_install: Can't mount /sdcard, 4 times
handle_cota_install: Can't mount /sdcard, 5 times

Can anyone tell me what is this?

xda-developers