Clean up code that directly imports nested classes like Builder, Entry, etc.

PiperOrigin-RevId: 195100670
GitOrigin-RevId: 94b8702db5f9a905337aca74bfc2e7c436bf33ec
Change-Id: Iea45a0d018d49a43181c1e357721d0b552bea777
3 files changed
tree: abcca77c7d825a4f70ff1e280c7497355c0985d2
  1. java/
  2. test/