[FIX] web: clear_uncommitted_changes on browser's back button

This is done by guarding the `on_hashchange` evant handler with the
`clear_uncommitted_changes` function.

Note that the url has already changed when we are in this handler, so we
make sure to restore the old url when the user chose to continue its
edition.

1 files changed, 24 insertions, 12 deletions

diff --git a/addons/web/static/src/js/web_client.js b/addons/web/static/src/js/web_client.js
index 48216f9c0a3..5498e0a7474 100644
--- a/addons/web/static/src/js/web_client.js
+++ b/addons/web/static/src/js/web_client.js
@@ -285,20 +285,32 @@ var WebClient = Widget.extend({
         }
     },
     on_hashchange: function(event) {
+        if (this._ignore_hashchange) {
+            this._ignore_hashchange = false;
+            return;
+        }
+
         var self = this;
-        var stringstate = event.getState(false);
-        if (!_.isEqual(this._current_state, stringstate)) {
-            var state = event.getState(true);
-            if(!state.action && state.menu_id) {
-                self.menu.is_bound.done(function() {
-                    self.menu.menu_click(state.menu_id);
-                });
-            } else {
-                state._push_me = false;  // no need to push state back...
-                this.action_manager.do_load_state(state, !!this._current_state);
+        this.clear_uncommitted_changes().then(function () {
+            var stringstate = event.getState(false);
+            if (!_.isEqual(self._current_state, stringstate)) {
+                var state = event.getState(true);
+                if(!state.action && state.menu_id) {
+                    self.menu.is_bound.done(function() {
+                        self.menu.menu_click(state.menu_id);
+                    });
+                } else {
+                    state._push_me = false;  // no need to push state back...
+                    self.action_manager.do_load_state(state, !!self._current_state);
+                }
             }
-        }
-        this._current_state = stringstate;
+            self._current_state = stringstate;
+        }, function () {
+            if (event) {
+                self._ignore_hashchange = true;
+                window.location = event.originalEvent.oldURL;
+            }
+        });
     },
     do_push_state: function(state) {
         this.set_title(state.title);