More rows.Close() and rows.Err() (#3262)

Looks like we missed some `rows.Close()`

Even though `rows.Err()` is mostly not necessary, we should be more
consistent in the DB layer.

[skip ci]

syncapi/storage/postgres/current_room_state_table.go

@@ -392,7 +392,7 @@ func currentRoomStateRowsToStreamEvents(rows *sql.Rows) ([]types.StreamEvent, er
 		})
 	}
 
-	return events, nil
+	return events, rows.Err()
 }
 
 func rowsToEvents(rows *sql.Rows) ([]*rstypes.HeaderedEvent, error) {

syncapi/storage/postgres/memberships_table.go

@@ -19,6 +19,7 @@ import (
 	"database/sql"
 	"fmt"
 
+	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	rstypes "github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/syncapi/storage/tables"
@@ -160,6 +161,7 @@ func (s *membershipsStatements) SelectMemberships(
 	if err != nil {
 		return
 	}
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectMemberships: failed to close rows")
 	var (
 		eventID string
 	)

syncapi/storage/postgres/peeks_table.go

@@ -164,7 +164,7 @@ func (s *peekStatements) SelectPeekingDevices(
 		devices = append(devices, types.PeekingDevice{UserID: userID, DeviceID: deviceID})
 		result[roomID] = devices
 	}
-	return result, nil
+	return result, rows.Err()
 }
 
 func (s *peekStatements) SelectMaxPeekID(

syncapi/storage/postgres/presence_table.go

@@ -144,7 +144,7 @@ func (p *presenceStatements) GetPresenceForUsers(
 		presence.ClientFields.Presence = presence.Presence.String()
 		result = append(result, presence)
 	}
-	return result, err
+	return result, rows.Err()
 }
 
 func (p *presenceStatements) GetMaxPresenceID(ctx context.Context, txn *sql.Tx) (pos types.StreamPosition, err error) {