Testing on Chrome with flash

I'm doing automated tests with Chrome.

Part of my suite needs flash to be activated (sight...).

I'm struggling to activate it. Here's what I got:

If I open a regular chrome session, with Flash checked in chrome://plugins, it works there:

When the tests start, the command line executed is:

▶ ps -edf | grep chrome
augustin 24752 24743  2 12:12 pts/0    00:00:07 /opt/google/chrome/chrome --user-data-dir=/tmp/karma-22735678 --no-default-browser-check --no-first-run --disable-default-apps --disable-popup-blocking --disable-translate --disable-background-timer-throttling http://ift.tt/2gELs6M

I always get Download failed or sometimes flash version outdated.

Even if I check flash in plugins and reload, even if I allow it specifically for this tab and refresh:

I tried several command line options:

• --always-authorize-plugins from there
• --enable-plugins from there

without sucess. :(

Thanks for the help