[Android] Remove dead code, fix the indicator position on load (#9502)

Author: rmarinho

Xamarin.Forms.Platform.Android/CollectionView/IndicatorViewRenderer.cs

@@ -198,18 +198,8 @@ void SetUpNewElement(IndicatorView newElement)
 				UpdateItemsSource();
 
 			ElevationHelper.SetElevation(this, newElement);
-		}
 
-		void IndicatorsViewItemSourcePropertyChanged(object sender, PropertyChangedEventArgs changedProperty)
-		{
-			if (changedProperty.Is(ItemsView.ItemsSourceProperty))
-			{
-				UpdateItemsSource();
-			}
-			else if (changedProperty.Is(SelectableItemsView.SelectedItemProperty))
-			{
-				UpdateSelectedIndicator();
-			}
+			UpdateSelectedIndicator();
 		}
 
 		void UpdateSelectedIndicator()