Validator Fix

[nisdas]

Resolves #903

This PR resolves the error by completely removing any appending of the specials records that occured when a new active state was calculated. Due to appending of 2 new special records each cycle transition, the first two active validators were logged out due to the following function in Casper

func ProcessSpecialRecords(slotNumber uint64, validators []*pb.ValidatorRecord, pendingSpecials []*pb.SpecialRecord) ([]*pb.ValidatorRecord, error) {
	// For each special record object in active state.
	for _, specialRecord := range pendingSpecials {

		// Covers validators submitted logouts from last cycle.
		if specialRecord.Kind == uint32(params.Logout) {
			validatorIndex := binary.BigEndian.Uint64(specialRecord.Data[0])
			exitedValidator := v.ExitValidator(validators[validatorIndex], slotNumber, false)
			validators[validatorIndex] = exitedValidator
			// TODO(#633): Verify specialRecord.Data[1] as signature. BLSVerify(pubkey=validator.pubkey, msg=hash(LOGOUT_MESSAGE + bytes8(version))
		}

	}
	return validators, nil
}

With special records added whenever CalculateNewActiveState was run, the following lines were removed to stop that from occuring

	_, proposerIndex, err := v.ProposerShardAndIndex(
		cState.ShardAndCommitteesForSlots(),
		cState.LastStateRecalculationSlot(),
		parentSlot)
	if err != nil {
		return nil, fmt.Errorf("could not get proposer index %v", err)
	}

	specialRecordData := make([][]byte, 2)
	for i := range specialRecordData {
		specialRecordData[i] = make([]byte, 32)
	}
	blockRandao := block.RandaoReveal()
	proposerIndexBytes := b.Bytes8(proposerIndex)
	specialRecordData[0] = proposerIndexBytes
	specialRecordData[1] = blockRandao[:]
 	newState.data.PendingSpecials = a.appendNewSpecialObject(&pb.SpecialRecord{
		Data: specialRecordData,
	})

[codecov]

Codecov Report

Merging #914 into master will decrease coverage by 0.13%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #914      +/-   ##
==========================================
- Coverage   73.22%   73.08%   -0.14%     
==========================================
  Files          69       69              
  Lines        4575     4559      -16     
==========================================
- Hits         3350     3332      -18     
- Misses        895      897       +2     
  Partials      330      330

[terencechain]

thanks a lot for the quick fix, we'll track adding special record back in #923