Created LauncherWidgetHolder as a wrapper for LauncherAppWidgetHost

The wrapper class is created for further changes that will run the wrapped host in the background.

Test: N/A
Bug: 235358918
Change-Id: I9bd6fc2749c5d4a4d3391fb75d0c3ff1e13d17bf
diff --git a/src/com/android/launcher3/SecondaryDropTarget.java b/src/com/android/launcher3/SecondaryDropTarget.java
index 0ee7aae..791cfff 100644
--- a/src/com/android/launcher3/SecondaryDropTarget.java
+++ b/src/com/android/launcher3/SecondaryDropTarget.java
@@ -288,7 +288,7 @@
             if (widgetId != INVALID_APPWIDGET_ID) {
                 mLauncher.setWaitingForResult(
                         PendingRequestArgs.forWidgetInfo(widgetId, null, info));
-                mLauncher.getAppWidgetHost().startConfigActivity(mLauncher, widgetId,
+                mLauncher.getAppWidgetHolder().startConfigActivity(mLauncher, widgetId,
                         REQUEST_RECONFIGURE_APPWIDGET);
             }
             return null;