This is an inline definition of a pretty rich object with non trivial methods. I think it will be way more readable to define a separate class like AndroidProjectFile (naming is up to you) and have this line look like this:
projectFileCache[project_dir] = new AndroidProjectFile(...);

I would even define the AndroidProjectFile class in a separate js file, this way other platforms similar to Android might reuse or subclass it if they want.
The windows8 parser does something similar with the util/w8jsproj.js

Otherwise LGTM.