clang-format: [Java] Fix line break behavior of class declarations.

Change breaking preferences:
1. Break before "extends"
2. Break before "implements"
3. Break within the implements list.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@221981 91177308-0d34-0410-b5e6-96231b3b80d8