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

PiperOrigin-RevId: 194985157
GitOrigin-RevId: 26ff4b3e3997aab79e39caf62c0d123a315d9478
Change-Id: Ibdf69191b559399f4775d82a52a26ce93567707c
1 file changed
tree: 9a463266076ed77fe27e23a218f1f3886acd3f95
  1. java/
  2. test/