@pozdnyakov as you pointed out, Crosswalk is a bit odd in keeping those objects in the "MainParts" which is more like an strategy object.

We don't need to change that, but if we are considering promoting XWalkContentBrowserClient into the "master" object holds the rest, it may be a good idea to add an acessor to RuntimeContext() there.

`RuntimeContext* runtime_context = XWalkContentBrowserClient::Get()->runtime_context();`

What do you think?