Adds support for OpenURI and Email Flatpak portals. To support them we
just do specific DBus calls, which are then caught and forwarded by
xdg-desktop-portal daemon/service. This is needed for Qt applications
running in sandbox, otherwise they cannot open links or email clients
inside sandbox. Other portal support, like for opening files can be
added into a platform theme, but adding support for OpenURI and Email
portal requires writing custom platform services plugin and this is only
possible when you write complete platform plugin, thus we want to have
this support directly in Qt. Support for other portals will most likely
follow soon, but at this moment we have to get rid of creating our
custom platform plugin to just have our own platform services for
flatpak support.
[ChangeLog][Platform Specific Changes][Linux] Added support for flatpak
portals. Flatpak is a software utility for software deployment and
package management. It provides a sandbox environment in which users
can run applications in isolation from the rest of the system. To
communicate with the system flatpak uses portals, which are designed to
be a bridge between sandboxed applications and desktop/system running on
user's computer. Flatpak runs automatically this as service, called
xdg-desktop-portal, which exports portals on DBus and which are by
default visible to all applications running under Flatpak.
Change-Id: Ice57ad120d30a3154b133172c79d8e9d6e61bd4c
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
c35c017a6c