message: Implement GetMetadata in DescriptorScriptPubKeyMan
diff: @@ -2038,6 +2038,19 @@ TransactionError DescriptorScriptPubKeyMan::FillPSBT(PartiallySignedTransaction&
  std::unique_ptr<CKeyMetadata> DescriptorScriptPubKeyMan::GetMetadata(const CTxDestination& dest) const
  {
  + std::unique_ptr<SigningProvider> provider = GetSigningProvider(GetScriptForDestination(dest));
  + if (provider) {
  + KeyOriginInfo orig;
  + CKeyID key_id = GetKeyForDestination(*provider, dest);
  + if (provider->GetKeyOrigin(key_id, orig)) {
  + LOCK(cs_desc_man);
  + std::unique_ptr<CKeyMetadata> meta = MakeUnique<CKeyMetadata>();
  + meta->key_origin = orig;
  + meta->has_key_origin = true;
  + meta->nCreateTime = m_wallet_descriptor.creation_time;
  + return meta;
  + }
  + }
  return nullptr;
  }
  