message: Change SourcePos printing style in favour of clang ast-dump
diff: @@ -2043,7 +2043,7 @@ llvm::DINamespace *SourcePos::GetDINamespace() const {
  }
  void SourcePos::Print() const {
  - printf(" @ [%s:%d.%d - %d.%d] ", name, first_line, first_column, last_line, last_column);
  + printf(" <%s:%d.%d - %d.%d> ", name, first_line, first_column, last_line, last_column);
  }
  bool SourcePos::operator==(const SourcePos &p2) const {
  