[FIX] stock: inventory adjustment

The inventory adjustment form is not suitable for large inventories.

First, a list view embedded in a form view is not convenient since it
doesn't provide any search capabilities. The user has to rely on the
search feature of the browser, which has restricted features in
comparison to the Odoo search field.

Then, the existing onchange mechanism coupled with computed fields
triggers heavy computations impacting all lines each time a single
line is modified. This leads to a hanging page for every inventory line
modification, which causes a non-negligeable loss of time.

This commit introduces a new tree view for inventory lines, accessible
thanks to a stat button on the inventory page. This button is available
in debug mode, if the inventory is in state 'Confirmed'. The tree view
contains the same fields than the tree view embedded in the form view,
without the flaws of the latter.

opw-760614

addons/stock/views/stock_inventory_views.xml

@@ -120,6 +120,19 @@
                 <field name="state" widget="statusbar" statusbar_visible="draft,confirm,done"/>
             </header>
             <sheet>
+                <div class="oe_button_box" name="button_box">
+                    <button name="action_inventory_line_tree"
+                        class="oe_stat_button"
+                        icon="fa-building-o"
+                        type="object"
+                        help="List view of lines"
+                        groups="base.group_no_one"
+                        states="confirm">
+                        <div class="o_form_field o_stat_info">
+                            <span class="o_stat_text">Details</span>
+                        </div>
+                    </button>
+                </div>
                 <div class="oe_title">
                     <label for="name" class="oe_edit_only"/>
                     <h1><field name="name" placeholder="e.g. Annual inventory"/></h1>
@@ -247,5 +260,15 @@
         </field>
     </record>
 
+    <record id="action_inventory_line_tree" model="ir.actions.act_window">
+        <field name="name">Inventory Lines</field>
+        <field name="type">ir.actions.act_window</field>
+        <field name="res_model">stock.inventory.line</field>
+        <field name="view_type">form</field>
+        <field name="view_mode">tree</field>
+        <field name="view_id" ref="stock_inventory_line_tree2"/>
+        <field name="domain">[('inventory_id', '=', active_id)]</field>
+    </record>
+
     <menuitem action="action_inventory_form" id="menu_action_inventory_form" parent="menu_stock_warehouse_mgmt" sequence="30"/>
 </odoo>