chromium: Fix building with WineVine components

Before version 54, the WideVine CDM plugin was built unconditionally and
it seems since version 54 this now is dependent upon a GYP/GN flag on
whether to include the CDM shared library or not.

Also, we now use a patch from Gentoo which should hopefully get the CDM
plugin to work properly, at least according to their bugtracker:

https://bugs.gentoo.org/show_bug.cgi?id=547630



Signed-off-by: aszlig <aszlig@redmoonstudios.org>