Refactoring ItemInfo

> Changing dragObject to ItemInfo
> Removing dropPos which is always null
> Removing requiresDbUpdate which is only used in CellLayout

Change-Id: I753ddaae0880c8a9bfee5a1266095ff34610284a
diff --git a/src/com/android/launcher3/FolderInfo.java b/src/com/android/launcher3/FolderInfo.java
index aea21c9..6e0dcd4 100644
--- a/src/com/android/launcher3/FolderInfo.java
+++ b/src/com/android/launcher3/FolderInfo.java
@@ -22,7 +22,6 @@
 import com.android.launcher3.compat.UserHandleCompat;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 
 /**
  * Represents a folder containing shortcuts or apps.
@@ -140,7 +139,7 @@
         return "FolderInfo(id=" + this.id + " type=" + this.itemType
                 + " container=" + this.container + " screen=" + screenId
                 + " cellX=" + cellX + " cellY=" + cellY + " spanX=" + spanX
-                + " spanY=" + spanY + " dropPos=" + Arrays.toString(dropPos) + ")";
+                + " spanY=" + spanY + ")";
     }
 
     public boolean hasOption(int optionFlag) {