Added ResizableFlowPanel to be able to fix hierarchical resizing

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/raceboard/ResizableFlowPanel.java

@@ -0,0 +1,23 @@
+package com.sap.sailing.gwt.ui.raceboard;
+
+import com.google.gwt.user.client.ui.FlowPanel;
+import com.google.gwt.user.client.ui.RequiresResize;
+import com.google.gwt.user.client.ui.Widget;
+import com.google.gwt.user.client.ui.WidgetCollection;
+
+/**
+ * Utility class extending {@link FlowPanel} and implementing {@link RequiresResize} interface. All
+ * {@link #getChildren() children} also implementing {@link RequiresResize} are informed by calling their
+ * {@link RequiresResize#onResize()} method.
+ */
+class ResizableFlowPanel extends FlowPanel implements RequiresResize {
+    @Override
+    public void onResize() {
+        WidgetCollection children = getChildren();
+        for (Widget widget : children) {
+            if (widget instanceof RequiresResize) {
+                ((RequiresResize) widget).onResize();
+            }
+        }
+    }
+}