message: Use murmur2_or_cityhash for ObjectId::hash()
diff: **************************************************************************/
  #include <realm/object_id.hpp>
  +#include <realm/string_data.hpp>
  #include <realm/util/assert.hpp>
  #include <atomic>
  #include <chrono>
  #include <random>
  -#include <string_view>
  using namespace std::chrono;
  @@ -115,8 +115,7 @@ std::string ObjectId::to_string() const
  size_t ObjectId::hash() const noexcept
  {
  - using string_view = std::basic_string_view<uint8_t>;
  - return std::hash<string_view>()(string_view(&m_bytes[12], sizeof m_bytes));
  + return murmur2_or_cityhash(m_bytes, sizeof(m_bytes));
  }
  