Virtual console in GTK input uses wrong color for dark gray
Description of problem:
The virtual console in the GTK window uses black to draw dark gray text. This becomes unintelligible if drawing on black background.
Steps to reproduce:
1. Boot any distro to shell prompt with `-serial vc`.
2. Switch to serial console in QEMU GTK window (Ctrl+Alt+3).
4. Run `echo -e "\e[1;30mDark Greay\e[m"`.
5. Output is black on black.

or

1. `qemu-system-x86_64 -bios /usr/share/edk2/x64/OVMF.fd`
2. Enter EFI internal shell
3. `cls 0 8`
4. Run `help cls` and observe correct colors in VGA window.
5. Switch to serial console and observe black on black colors.