I do not want to ship a built-in plugin for whom there is nobody officially maintaining it. We used to maintain the plugin, but Ludei repeatedly broke it and failed to provide any kind of guidance on how to update it, so we gave up and told them to maintain it. Then they released it on github for "the community to support" which we took to mean they were not interested in maintaining it either. On top of that, the version they released on github has been broken and is now incompatible with the one we ship with Construct 2: they mangled all the plugin IDs so old projects using the old plugin can no longer open with the new plugin - it will either fail to open or corrupt the project. They presumably did not read our documentation that states you cannot change the plugin IDs after release (link, "A number uniquely identifying this... saved to the project XML, so you may change the rest of the parameters after releasing your plugin, but not the id.").
So updating the plugin means breaking lots of existing projects and having no clear owner for maintenance to address things like new features and bug reports, which there inevitably will be. This does not meet the quality bar that we set for official features.
On top of that CocoonJS has various bugs and incompatibilities that Ludei have never fixed, despite my repeated attempts to contact them and guide them to solutions so users don't have to keep running in to the same old things (memory management being an excellent example of this). Overall users appear to be having a bad time with CocoonJS, and Ludei have made it almost impossible for us to easily support it, and this repeatedly reflects badly on us as well since it adds to the reputation that "mobile support doesn't work" (where Crosswalk and Ejecta ought to be working better). So at this point to be honest I am thinking more about deprecating support for it than making any motions to keep supporting it. Deprecating means the same thing as happened to the Intel AGI: it's hidden by default so new users are discouraged from going down that route, but for users who need to keep using it for existing projects (or have figured out a way through all the problems) can do so by right-clicking and showing the deprecated options. We'll work hard to get any bugs or missing features sorted out in Ejecta and Crosswalk. And with Android L and iOS 8 on the cusp of coming out in a couple of months, PhoneGap will be a great solution from then on too, which I think is the ultimate solution and allows us to get rid of this minefield of non-browser engines once and for all.