clang-format: Fix braced list detection.

Before:
  static_assert(std::is_integral<int> {} + 0, "");
  int a = std::is_integral<int> {}
  + 0;

After:
  static_assert(std::is_integral<int>{} + 0, "");
  int a = std::is_integral<int>{} + 0;

llvm-svn: 209431