clang-format: [Java] Improve formatting of generics.

Before:
  Function < F, ? extends T > function;

After:
  Function<F, ? extends T> function;

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@221976 91177308-0d34-0410-b5e6-96231b3b80d8