Add ModifiersChanged message on Tab and keep value

The message is forwarded from app/dialog Message, and used to
keep the value of the status of modifiers in Tab.

src/app.rs

@@ -2629,6 +2629,11 @@ impl Application for App {
             },
             Message::ModifiersChanged(modifiers) => {
                 self.modifiers = modifiers;
+                let entity = self.tab_model.active();
+                return self.update(Message::TabMessage(
+                    Some(entity),
+                    tab::Message::ModifiersChanged(modifiers),
+                ));
             }
             Message::MounterItems(mounter_key, mounter_items) => {
                 // Check for unmounted folders

src/dialog.rs

@@ -1292,6 +1292,9 @@ impl Application for App {
             }
             Message::ModifiersChanged(modifiers) => {
                 self.modifiers = modifiers;
+                return self.update(Message::TabMessage(tab::Message::ModifiersChanged(
+                    modifiers,
+                )));
             }
             Message::MounterItems(mounter_key, mounter_items) => {
                 // Check for unmounted folders

src/tab.rs

@@ -1257,6 +1257,7 @@ pub enum Message {
     ItemUp,
     Location(Location),
     LocationUp,
+    ModifiersChanged(Modifiers),
     Open(Option<PathBuf>),
     RightClick(Option<usize>),
     MiddleClick(usize),
@@ -1898,6 +1899,7 @@ pub struct Tab {
     select_range: Option<(usize, usize)>,
     clicked: Option<usize>,
     selected_clicked: bool,
+    modifiers: Modifiers,
     last_right_click: Option<usize>,
     search_context: Option<SearchContext>,
     global_cursor_position: Option<Point>,
@@ -1994,6 +1996,7 @@ impl Tab {
             clicked: None,
             dnd_hovered: None,
             selected_clicked: false,
+            modifiers: Modifiers::default(),
             last_right_click: None,
             search_context: None,
             global_cursor_position: None,
@@ -3034,6 +3037,9 @@ impl Tab {
                     }
                 }
             }
+            Message::ModifiersChanged(modifiers) => {
+                self.modifiers = modifiers;
+            }
             Message::Open(path_opt) => {
                 match path_opt {
                     Some(path) => {