android-sdk: Certain files are lost on upgrade

Currently, the android-sdk will install the platform-tools and build-tools into 2 directories that should be outside of the android-sdk cellar, but are not.

Because of this, on an upgrade of the android-sdk, any installations of the platform-tools and build-tools will be lost.

The attached patch fixes this by adding the two additional directories to the existing list of preserved data directories.
Is there an easy way to uninstall them? I guess I'm wondering if people keep upgrading if they'll have all this cruft they'll need to clean up manually?