@kjhodge, that's pretty cool!
btw if its webapp development you are after, you actually don't even need to go through with flashing webOS onto an RPi.
If you head over to the webOS TV developer site you could get the SDK that comes with the TV emulators that run on VBox. All the tools you ever need come bundled in that kit.
You can either use the Ares CLI tool or the Eclipse based IDE to create, package and deploy the app onto either an emulator or even an actual TV on the same network!
You could also use the recently released QEMU emulator, but unfortunately I haven't used that to comment on it.
I suggest looking into ES2015, that's the latest iteration of JS. It has a ton more features than ES5(the last iteration and mostly used one) and is generally more mature. I'm also still going through some syntax changes in ES2015 and having bit of a hard time since it's sort of like relearning the language over again. If you're new the JS as a whole it could be vastly easier for you and learning ES2015 will open up whole other avenues like React Native development.
Hope this comes handy. This is basically the stuff I wished someone told me when I started out