Impacted versions:
At least version 10, version 11(Can only re-produce the problem sometimes)

Steps to reproduce:
Please see this screencast recorded on odoo runbot.
https://youtu.be/cSPQvp9jQJc

Current behavior:
When users search by account in Journal Entries List View. A special value "dummy_account_id" is set in context, in order to facilitate search by account on account.move level.
With this context value , when users create a journal entries, the system will add default value before the creation.

https://github.com/odoo/odoo/blob/fc69b37cf710623ea215cd085e998679d8c50985/odoo/models.py#L3802

This method will set "dummy_account_id" to the previously searched account in vals.

Then the system continue creating account.move and related account.move.line records.
It is fine until the system run this:
https://github.com/odoo/odoo/blob/fc69b37cf710623ea215cd085e998679d8c50985/odoo/models.py#L3830

Since "dummy_account_id" is related field, and it now has value. The system will change the first related  account.move.line record to dummy_account_id.

Eventualy, the account is wrongly set to "dummy_account_id".

Expected behavior:
This is a feature which will fill the form field value with searched value for users. But the journal entry creation should not be affected by dummy_account_id, since it is only for searching purpose.

@Yenthe666 Would you please review this issue and help to bring related odoo staff to this issue?
]
                str_domain = expression.OR([str_domain, amount_domain])
            except:
                pass
            
            
            if 'bank_statement_line' in context and not context['bank_statement_line'].partner_id.id:
                str_domain = expression.OR([str_domain, [('partner_id.name', 'ilike', str)]])
            domain = expression.AND([domain, str_domain])
        return domain
    def _domain_move_lines_for_manual_reconciliation(self, account_id, partner_id=False, excluded_ids=None, str=False):
        """ Create domain criteria that are relevant to manual reconciliation. """
        domain = ['&', ('reconciled', '=', False), ('account_id', '=', account_id)]
        if partner_id:
            domain = expression.AND([domain, [('partner_id', '=', partner_id)]])
        generic_domain = self.domain_move_lines_for_reconciliation(excluded_ids=excluded_ids, str=str)
        return expression.AND([generic_domain, domain])
    @api.model
    def get_move_lines_for_manual_reconciliation(self, account_id, partner_id=False, excluded_ids=None, str=False, offset=0, limit=None, target_currency_id=False):
        """ Returns unreconciled move lines for an account or a partner+account, formatted for the manual reconciliation widget """
        domain = self._domain_move_lines_for_manual_reconciliation(account_id, partner_id, excluded_ids, str)
        lines = self.search(domain, offset=offset, limit=limit, order="date_maturity asc, id asc")
        if target_currency_id:
            target_currency = self.env['res.currency'].browse(target_currency_id)
        else:
            account = self.env['account.account'].browse(account_id)
            target_currency = account.currency_id or account.company_id.currency_id
        return lines.prepare_move_lines_for_reconciliation_widget(target_currency=target_currency)
    @api.multi
    def prepare_move_lines_for_reconciliation_widget(self, target_currency=False, target_date=False):