Revert "Reverting refactoring of Folder and FolderIcon to avoid dependencies breakage"

This reverts commit fc956e5a2a818c06ed3424e15b0aa20a3f604658.

Change-Id: Ib3b5156b8fc3cad35c4634d61d5390c848ce1f93
diff --git a/src/com/android/launcher3/DeleteDropTarget.java b/src/com/android/launcher3/DeleteDropTarget.java
index 173e6ab..997ded2 100644
--- a/src/com/android/launcher3/DeleteDropTarget.java
+++ b/src/com/android/launcher3/DeleteDropTarget.java
@@ -24,6 +24,7 @@
 import android.view.animation.AnimationUtils;
 
 import com.android.launcher3.dragndrop.DragLayer;
+import com.android.launcher3.folder.Folder;
 import com.android.launcher3.util.FlingAnimation;
 import com.android.launcher3.util.Thunk;