deoplete-go can't deal with files open with Netrw

[glacambre]

I recently tried to open a file over the scp:// protocol which is handled by Vim's "Netrw" plugin. When trying to autocomplete a word, the message[deoplete] gocode panicked is shown.
Here are the steps to reproduce the bug when deoplete and deoplete-go are loaded in your vimrc:

nvim scp://server//tmp/tmp.go
:set ft=go
a
fmt

This will open a file with Netrw, set the filetype to "go", enter insert mode and type "fmt". The message

match 1 of 6
[deoplete] gocode panicked

will then be shown and the autocompletion popup won't be shown.
I believe this is a bug with deoplete-go because other autocompletion plugins (deoplete-jedi for example) do not have this problem.

[Shougo]

The file in the remote server is not supported.
And it is hard to test.

[Shougo]

I will fix the problem.