Enforce same keyboard behaviour as tryton

- down key put the focus on the menu
- return key does not open the menu
- escape key does not close modal

issue7296
review37181002

src/common.js

@@ -3063,14 +3063,24 @@
             this.input.keydown(function(evt) {
                 if (evt.which == Sao.common.ESC_KEYCODE) {
                     if (this.dropdown.hasClass('open')) {
+                        evt.preventDefault();
+                        evt.stopPropagation();
                         this.menu.dropdown('toggle');
                     }
-                } else if (evt.which == Sao.common.RETURN_KEYCODE) {
-                    if (!this.dropdown.hasClass('open')) {
-                        this.menu.dropdown('toggle');
+                } else if (evt.which == Sao.common.DOWN_KEYCODE) {
+                    if (this.dropdown.hasClass('open')) {
+                        evt.preventDefault();
+                        this.menu.find('li > a').first().focus();
                     }
                 }
             }.bind(this));
+            this.menu.keydown(function(evt) {
+                if (evt.which == Sao.common.ESC_KEYCODE) {
+                    evt.preventDefault();
+                    evt.stopPropagation();
+                    this.menu.dropdown('toggle');
+                }
+            }.bind(this));
             // We must set the overflow of the treeview containing the input to
             // visible to prevent vertical scrollbar inherited from the auto
             // overflow-x

src/sao.js

@@ -607,6 +607,14 @@ var Sao = {};
                     this.update.bind(this),
                     this.match_selected.bind(this),
                     this.format.bind(this));
+            completion.input.keydown(function(evt) {
+                if (evt.which == Sao.common.RETURN_KEYCODE) {
+                    if (!completion.dropdown.hasClass('open')) {
+                        evt.preventDefault();
+                        completion.menu.dropdown('toggle');
+                    }
+                }
+            });
         },
         format: function(content) {
             var el = jQuery('<div/>');