Cleaning up LauncherModel

- performing all DB operations immediately if called from worker thread (a previous change that did this in updateItemInDatabase fixed an outstanding bug)
- centralizing logic to do database updates
- removing old logging code

Change-Id: Idc7bfef3921828ff7c5492b8e996c0a07e1ec508
diff --git a/src/com/android/launcher2/ItemInfo.java b/src/com/android/launcher2/ItemInfo.java
index 5c05f16..8d46624 100644
--- a/src/com/android/launcher2/ItemInfo.java
+++ b/src/com/android/launcher2/ItemInfo.java
@@ -86,16 +86,10 @@
      */
     int[] dropPos = null;
 
-    /*
-     *  A tag to know where this item was created
-     */
-    String whereCreated;
-
-    ItemInfo(String whereCreated) {
-        this.whereCreated = whereCreated;
+    ItemInfo() {
     }
 
-    ItemInfo(ItemInfo info, String whereCreated) {
+    ItemInfo(ItemInfo info) {
         id = info.id;
         cellX = info.cellX;
         cellY = info.cellY;
@@ -104,7 +98,6 @@
         screen = info.screen;
         itemType = info.itemType;
         container = info.container;
-        this.whereCreated = whereCreated;
     }
 
     /**