[FIX] web: list editable: no flicker when editing

The test checking that the cells width remains the same when
entering the edition mode was broken, because we didn't hardcode
the width for readonly cells.

This commit ensures that we force the width of all the cells of
the edited row.

addons/web/static/src/js/views/list/list_editable_renderer.js

@@ -263,10 +263,6 @@ ListRenderer.include({
             return;
         }
         var $td = this._findTd($row, colIndex);
-        // force the width of the cell to its current value so that it won't
-        // change if its content changes (to prevent the list view from
-        // flickering).
-        $td.width($td.width());
         var widget_keys = ['list.' + field.type, field.type];
         if (node.attrs.widget) {
             widget_keys.unshift(node.attrs.widget);
@@ -385,6 +381,12 @@ ListRenderer.include({
         // instantiate column widgets
         var $row = this.$('tbody tr').eq(rowIndex);
         $row.addClass('o_selected_row');
+        // force the width of each cell to its current value so that it won't
+        // change if its content changes, to prevent the view from flickering
+        $row.find('td').each(function () {
+            var $td = $(this);
+            $td.width($td.width());
+        });
 
         _.each(this.columns, function (node, index) {
             var widget = self._renderFieldWidget($row, node, rowIndex, index);