Prompt to set URI wallpapers on lock screen (missed before).

Change-Id: I5328a9861ce2843aba36ecad172eb0e364a816a0
diff --git a/WallpaperPicker/src/com/android/launcher3/WallpaperCropActivity.java b/WallpaperPicker/src/com/android/launcher3/WallpaperCropActivity.java
index 364cdb8..2f21145 100644
--- a/WallpaperPicker/src/com/android/launcher3/WallpaperCropActivity.java
+++ b/WallpaperPicker/src/com/android/launcher3/WallpaperCropActivity.java
@@ -473,7 +473,7 @@
         if (onBitmapCroppedHandler != null) {
             cropTask.setOnBitmapCropped(onBitmapCroppedHandler);
         }
-        cropTask.execute();
+        NycWallpaperUtils.executeCropTaskAfterPrompt(this, cropTask, getOnDialogCancelListener());
     }
 
     protected void updateWallpaperDimensions(int width, int height) {