init navbar components

src/app/browser/main/tab/page/navigation/bookmark.rs

@@ -0,0 +1,22 @@
+use gtk::Button;
+
+pub fn new() -> Button
+{
+    let button = Button::builder()
+
+        .icon_name(
+            "starred-symbolic"
+        )
+
+        .tooltip_text(
+            "Toggle bookmark"
+        )
+
+        .sensitive(
+            false
+        )
+
+        .build();
+
+    return button;
+}