Linux UI: Add IsVisibleOnAllWorkspaces()

ui/views/widget/native_widget_aura.cc

Index: ui/views/widget/native_widget_aura.cc
diff --git a/ui/views/widget/native_widget_aura.cc b/ui/views/widget/native_widget_aura.cc
index a455eddf26809e303c101406e72dd02b59b10ab7..a2b790bc0d1db9c354bec41b49f85fdcf737c341 100644
--- a/ui/views/widget/native_widget_aura.cc
+++ b/ui/views/widget/native_widget_aura.cc
@@ -562,6 +562,10 @@ void NativeWidgetAura::SetVisibleOnAllWorkspaces(bool always_visible) {
   // Not implemented on chromeos or for child widgets.
 }
 
+bool NativeWidgetAura::IsVisibleOnAllWorkspaces() const {
+  return false;
+}
+
 void NativeWidgetAura::Maximize() {
   if (window_)
     window_->SetProperty(aura::client::kShowStateKey, ui::SHOW_STATE_MAXIMIZED);