clang-format: Fix incorrect braced init identification.

Before:
  int foo(int i) {
    return fo1 {}
    (i);
  }
  int foo(int i) {
    return fo1 {}
    (i);
  }

After:
  int foo(int i) { return fo1{}(i); }
  int foo(int i) { return fo1{}(i); }

This fixes llvm.org/PR19812.