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

PiperOrigin-RevId: 195040539
GitOrigin-RevId: 0a57d3dcb1cc014d65dbeb604035bb34a7191e29
Change-Id: I78ff7b0f225fbdcdeed44145fe0e28ffc0e4c197
2 files changed
tree: 863468c2231e372cbba704fe117c19027d8d8012
  1. java/
  2. test/