Unsupported scheme ‘socks5’ while emerging

[younis]

Hello, i am using a socks5 proxy,
and i have already it deployed locally:

2016/02/06 09:47:27 available remote server 107.***.***.164:3538(*** is shadowed my server address)
2016/02/06 09:47:27 starting local socks5 server at :1080 ...

in my firefox, i added a proxy config as below:

Give It a Name: Proxy Host: Port: socks5
shadowsocks 127.0.0.1 1080 *
(* for a choosed protocol)

it works perfectly on my device, i can visit google.
but if i use

export https_proxy="socks5://127.0.0.1:1080"

to emerge google-chrome, in /var/log/emerge-fetch.log, it shows:

Error parsing proxy URL socks5://127.0.0.1:1080: Unsupported scheme ‘socks5’.

and in my local proxy client log file, there is :
2016/02/06 10:33:20 socks handshake: socks version not supported

how can i enable the https_proxy through socks5? It will be a great benefit to me if i have chrome installed, i tried to install a standalone .deb file, i failed several times and even spoiled my system, i have reinstall system for several times.