The software also isn't in the preferred form for modification. The build system which runs Git commands and doesn't work as intended without it. You have to make a Git repository for it to work and there's meant to be a separate one for each separate component. It spews out errors.
So right now I think we all probably do not know. Google MIGHT refuse to release the source code, but it could release it - we don't know yet. Someone has to test that.
That would be a violation of the license terms. All Google has done so far is, apparently, to make it hella annoying to access the source code (but not impossible).