The topic is old but it's worth mentionning the more recent solutions to this :

• WPEWebkit : it comes with a small launcher named cog, it's fully open-source, and it supports URI scheme handling (see this presentation) in C/C++. It has several supported back-ends, amongst which is running directly on DRM.

Also, I advise anyone to keep an eye on saucer ; it is originally a [very modern] C++ webview library that allows you to build cross-platform desktop applications. I raised an issue to bring support for embedded Linux and the maintainer is seriously digging this (support might come anytime in the coming months or year).