implement separated mod with options for failure component

src/app/browser/window/tab/item/page/content/status.rs

@@ -1,6 +1,8 @@
 mod failure;
+mod loading;
 
 use failure::Failure;
+use loading::Loading;
 
 use adw::StatusPage;
 
@@ -9,14 +11,26 @@ pub struct Status {
 }
 
 impl Status {
-    // Construct
-    pub fn new_error(title: &str, description: &str) -> Self {
+    // Constructors
+
+    /// Create new default failure component
+    pub fn new_failure(title: Option<&str>, description: Option<&str>) -> Self {
         Self {
-            gobject: Failure::new(title, description),
+            gobject: Failure::new(title, description).gobject().clone(),
+        }
+    }
+
+    /// Create new default loading component
+    ///
+    /// Useful as the placeholder widget for async operations
+    pub fn new_loading(title: Option<&str>, description: Option<&str>) -> Self {
+        Self {
+            gobject: Loading::new(title, description).gobject().clone(),
         }
     }
 
     // Getters
+
     pub fn gobject(&self) -> &StatusPage {
         &self.gobject
     }