Clear should not show after Widget Configuration activity

Bug: 119847865

TL;DR;;
When configuration activity starts, simply make everything in drop
target bar invisible.

Change-Id: I37d067168368de4ee43b54e5dc95f958f5e94623

src/com/android/launcher3/DropTargetBar.java

@@ -204,7 +204,7 @@ public class DropTargetBar extends FrameLayout
         return visibleCount;
     }
 
-    private void animateToVisibility(boolean isVisible) {
+    public void animateToVisibility(boolean isVisible) {
         if (mVisible != isVisible) {
             mVisible = isVisible;