updateAvailable ObservableValue to BooleanBinding

src/main/java/org/cryptomator/ui/mainwindow/MainWindowTitleController.java

@@ -15,7 +15,6 @@ import javax.inject.Inject;
 import javafx.beans.binding.Bindings;
 import javafx.beans.binding.BooleanBinding;
 import javafx.beans.property.ReadOnlyBooleanProperty;
-import javafx.beans.value.ObservableValue;
 import javafx.fxml.FXML;
 import javafx.scene.input.MouseButton;
 import javafx.scene.layout.HBox;
@@ -31,7 +30,7 @@ public class MainWindowTitleController implements FxController {
 	private final FxApplicationWindows appWindows;
 	private final boolean trayMenuInitialized;
 	private final UpdateChecker updateChecker;
-	private final ObservableValue<Boolean> updateAvailable;
+	private final BooleanBinding updateAvailable;
 	private final LicenseHolder licenseHolder;
 	private final Settings settings;
 	private final BooleanBinding showMinimizeButton;
@@ -127,7 +126,7 @@ public class MainWindowTitleController implements FxController {
 		return licenseHolder;
 	}
 
-	public ObservableValue<Boolean> updateAvailableProperty() {
+	public BooleanBinding updateAvailableProperty() {
 		return updateAvailable;
 	}