clang-format: Fix formatting bug with comment in weird place.

Before:
  template <typename T>
  // T should be one of {A, B}.
      void f() {}

After:
  template <typename T>
  // T should be one of {A, B}.
  void f() {}

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191492 91177308-0d34-0410-b5e6-96231b3b80d8