update update_verifier comments

#include <functional>

#include <map>

#include <string>

#include <vector>

#include <snapuserd/snapuserd_client.h>

#include "otautil/rangeset.h"

// During the verification, it reads all the blocks in the care_map. And if a failure happens,

// it rejects the current boot and triggers a fallback.

// Note that update_verifier should be backward compatible to not reject care_map.txt from old

// releases, which could otherwise fail to boot into the new release. For example, we've changed

// the care_map format between N and O. An O update_verifier would fail to work with N care_map.txt.

// This could be a result of sideloading an O OTA while the device having a pending N update.

int update_verifier(int argc, char** argv);

// The UpdateVerifier parses the content in the care map, and continues to verify the

 public:

  UpdateVerifier();

  // This function tries to process the care_map.pb as protobuf message; and falls back to use

  // care_map.txt if the pb format file doesn't exist. If the parsing succeeds, put the result

  // of the pair <partition_name, ranges> into the |partition_map_|.

  // This function tries to process the care_map.pb as protobuf message. If the parsing succeeds,

  // put the result of the pair <partition_name, ranges> into the |partition_map_|.

  bool ParseCareMap();

  // Verifies the new boot by reading all the cared blocks for partitions in |partition_map_|.