GPL says we need to be provided with the preferred form for modification. Those are the Git repositories for Android source code.

For Pixel kernel drivers, Google is converting the source code from the preferred form of dozens of Git repositories to a massive monolithic tarball. The build system used for this code expects it to be a bunch of Git repositories and spews out errors without it. It does build the code but it isn't the build process they used to do it themselves which is non-compliance. We need to be provided with what is needed to build it in the same way they built it.