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?
account_id = (amount > 0 and tax_vals['account_id'] or tax_vals['refund_account_id'])
                    if not account_id: account_id = vals['account_id']
                    temp = {
                        'account_id': account_id,
                        'name': vals['name'] + ' ' + tax_vals['name'],
                        'tax_line_id': tax_vals['id'],
                        'move_id': vals['move_id'],
                        'partner_id': vals.get('partner_id'),
                        'statement_id': vals.get('statement_id'),
                        'debit': tax_vals['amount'] > 0 and tax_vals['amount'] or 0.0,
                        'credit': tax_vals['amount'] < 0 and -tax_vals['amount'] or 0.0,
                        'analytic_account_id': vals.get('analytic_account_id') if tax.analytic else False,
                    }
                    bank = self.env["account.bank.statement"].browse(vals.get('statement_id'))
                    if bank.currency_id != bank.company_id.currency_id:
                        ctx = {}
                        if 'date' in vals:
                            ctx['date'] = vals['date']
                        temp['currency_id'] = bank.currency_id.id
                        temp['amount_currency'] = bank.company_id.currency_id.with_context(ctx).compute(tax_vals['amount'], bank.currency_id, round=True)
                    tax_lines_vals.append(temp)
        new_line = super(AccountMoveLine, self).create(vals)
        for tax_line_vals in tax_lines_vals:
            # TO
            self.with_context(context).create(tax_line_vals)
        if self._context.get('check_move_validity', True):
            move.with_context(context)._post_validate()
        return new_line
    @api.multi
    def unlink(self):