Move revealers access away from base classes

Those should not appear in base classes, as they are available in main app only

src/app.js

@@ -1,4 +1,4 @@
-const { Gio, GObject, Gtk } = imports.gi;
+const { Gio, GObject, Gdk, Gtk } = imports.gi;
 const { AppBase } = imports.src.appBase;
 const { Widget } = imports.src.widget;
 const Debug = imports.src.debug;
@@ -43,6 +43,22 @@ class ClapperApp extends AppBase
         this._openFilesAsync(files).then(() => this.activate()).catch(debug);
     }
 
+    _onIconThemeChanged(gtkSettings)
+    {
+        super._onIconThemeChanged(gtkSettings);
+
+        const display = Gdk.Display.get_default();
+        if(!display) return;
+
+        const iconTheme = Gtk.IconTheme.get_for_display(display);
+        if(!iconTheme) return;
+
+        const { headerBar } = this.active_window.child.revealerTop;
+        if(!headerBar) return;
+
+        headerBar._onIconThemeChanged(iconTheme);
+    }
+
     _onWindowMap(window)
     {
         window.disconnect(this.mapSignal);

src/appBase.js

@@ -1,4 +1,4 @@
-const { Gio, GLib, GObject, Gdk, Gtk } = imports.gi;
+const { Gio, GLib, GObject, Gtk } = imports.gi;
 const Debug = imports.src.debug;
 const FileOps = imports.src.fileOps;
 const Misc = imports.src.misc;
@@ -131,16 +131,5 @@ class ClapperAppBase extends Gtk.Application
         }
         else if(hasAdwIcons)
             window.remove_css_class('adwicons');
-
-        const display = Gdk.Display.get_default();
-        if(!display) return;
-
-        const iconTheme = Gtk.IconTheme.get_for_display(display);
-        if(!iconTheme) return;
-
-        const { headerBar } = window.child.revealerTop;
-        if(!headerBar) return;
-
-        headerBar._onIconThemeChanged(iconTheme);
     }
 });

src/headerbar.js

@@ -28,4 +28,12 @@ class ClapperHeaderBar extends HeaderBarBase
     {
         this.root.fullscreen();
     }
+
+    _onIconThemeChanged(iconTheme)
+    {
+        super._onIconThemeChanged(iconTheme);
+
+        const { controlsRevealer } = this.root.child;
+        this._updateFloatIcon(!controlsRevealer.reveal_child);
+    }
 });

src/headerbarBase.js

@@ -245,16 +245,11 @@ class ClapperHeaderBarBase extends Gtk.Box
 
     _onIconThemeChanged(iconTheme)
     {
-        /* Those icons are relatively new,
-         * so check if theme has them */
+        /* Those icons are new, so check if theme has them */
         this.hasPipIcons = (
             iconTheme.has_icon('pip-in-symbolic')
             && iconTheme.has_icon('pip-out-symbolic')
         );
-
-        const { controlsRevealer } = this.root.child;
-
-        this._updateFloatIcon(!controlsRevealer.reveal_child);
     }
 });