[FIX] base: set current company as default for currency rates

When manually creating/importing a currency rate, there is no default
on the company_id field.

This is quite unfortunate, as rates are filtered by company then by
date, which means that a rate without company will never be taken
into account despite being newer. This filter makes sense for multi
company setups, but for mono-company setups this is quite annoying.

This commit adds a default on the company_id and adds a view for
the base_currency_rate model to only display the company field in
multi company settings.

openerp/addons/base/res/res_currency.py

@@ -282,6 +282,7 @@ class res_currency_rate(osv.osv):
     }
     _defaults = {
         'name': lambda *a: time.strftime('%Y-%m-%d 00:00:00'),
+        'company_id': lambda s, cr, uid, ctx=None: s.pool['res.users']._get_company(cr, uid, context=ctx)
     }
     _order = "name desc"
 

openerp/addons/base/res/res_currency_view.xml

@@ -23,6 +23,28 @@
             </field>
         </record>
 
+        <record id="view_currency_rate_form" model="ir.ui.view">
+            <field name="name">res.currency.rate.form</field>
+            <field name="model">res.currency.rate</field>
+            <field name="arch" type="xml">
+                <form string="Currency Rate">
+                    <sheet>
+                        <group>
+                            <group>
+                                <field name="name"/>
+                                <field name="rate"/>
+                            </group>
+                            <group>
+                                <field name="currency_id"/>
+                                <field name="company_id" groups="base.group_multi_company"/>
+                            </group>
+
+                        </group>
+                    </sheet>
+                </form>
+            </field>
+        </record>
+
         <act_window
            id="act_view_currency_rates"
            name="Currency Rates"