TAB completion of filenames beginning with colon is broken

[Jason Tyler]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -g -O2 -fdebug-prefix-map=/build/bash-LQgi2O/bash-5.0=.
-fstack-protector-strong -Wform$
uname output: Linux jpt 5.0.0-16-generic #17-Ubuntu SMP Wed May 15 10:52:21
UTC 2019 x86_64 x86_64 x86_64 G$
Machine Type: x86_64-pc-linux-gnu

Bash Version: 5.0
Patch Level: 3
Release Status: release

Description:
if a filename begins with ":", then tab completion will turn the colon into
":\:"

Repeat-By:
touch ./:
type "ls :<TAB>" to have the command completed to "ls :\:"