Fix bug where compose storage wasn't cleared on page unload (#1489818)

CHANGELOG

@@ -57,6 +57,7 @@ CHANGELOG Roundcube Webmail
 - Fix Delete button state after deleting identity/response (#1489972)
 - Fix bug where contacts with no email address were listed on compose addressbook (#1489970)
 - Fix images import from various vCard formats (#1489977)
+- Fix bug where compose storage wasn't cleared on page unload (#1489818)
 
 RELEASE 1.0.1
 -------------

program/js/app.js

@@ -655,9 +655,6 @@ function rcube_webmail()
     if (this.task == 'mail' && this.env.action == 'compose' && $.inArray(command, this.env.compose_commands) < 0 && !this.env.server_error) {
       if (this.cmp_hash != this.compose_field_hash() && !confirm(this.get_label('notsentwarning')))
         return false;
-
-      // remove copy from local storage if compose screen is left intentionally
-      this.remove_compose_data(this.env.compose_id);
     }
 
     this.last_command = command;
@@ -3803,6 +3800,11 @@ function rcube_webmail()
           ref.compose_type_activity_last = ref.compose_type_activity;
         }
       }, 5000);
+
+      // remove data from local storage if compose screen is left
+      $(window).unload(function() {
+        ref.remove_compose_data(ref.env.compose_id);
+      });
     }
 
     // Unlock interface now that saving is complete