message: fix simple_zip formatting
diff: #include <zlib.h>
  +#include <algorithm>
  #include <cstdio>
  #include <memory>
  #include <string>
  @@ -91,6 +92,15 @@ class HeaderWriter {
  const char *begin_;
  char *pos_;
  };
  +
  +// Returns the value clamped to the [low, high] interval. If the value is in the
  +// interval, returns the value. Otherwise returns low or high depending which
  +// one is closer.
  +// TODO(ikr): Repace with std::clamp once we move to c++17
  +inline int Clamp(int value, int low, int high) {
  + return std::min(std::max(value, low), high);
  +}
  +
  } // namespace
  struct Encoder::Impl {
  @@ -102,9 +112,7 @@ struct Encoder::Impl {
  };
  Impl(int compression_level, ByteSink out)
  - : compression_level_(compression_level < 0 ? 0
  - : compression_level > 9 ? 9
  - : compression_level),
  + : compression_level_(Clamp(compression_level, 0, 9)),
  delegate_write_(std::move(out)),
  out_([this](absl::string_view s) {
  output_file_offset_ += s.size(); // Keep track of offsets.
  