Adds README.version, README.google, MODULE_LICENSE_APACHE2 files
as required by the process (see b/30087411).

The code does not yet compile; it requires patching to work with
Android API and JUnit 4.10. Those patches will be added in
separate commits to make it easy to identify the Android
specific changes. All the changes will be submitted together.

Bug: 30244565
Change-Id: Icf556377478c3afdd644c5e4db0ff18898f496ae
Test: Once it compiles the tests will be run.