jdkPortable and OpenJDK Portable, and perhaps some other apps as well, are unique in how they install their folders as subfolders under CommonFiles.
But this seems to make the platform ignore their existence, meaning they don't show up in the platform's menu at all.
With that said, they do get to auto update, so it seems like a virus in that you get prompt to update them even though they don't appear installed.
Kind of a weird situation, not here and not there. Of course it also means the only way to uninstall those apps is to manually delete their folders.
They're not apps, they're common stuff used by other apps. By design, they have no icon in the menu. At some point the ability to 'manage' the common files will be added. For now, just manually delete the folders.
Sometimes, the impossible can become possible, if you're awesome!
It happened because I forgot I installed them, and didn't understand why every once in a while the platform wants to update something I've supposedly never installed. Usually I just approve, but this time I decided to investigate and found those folders.