Use Long.compare() instead of truncating values for comparison.

Bug: 24116808
diff --git a/src/com/android/launcher3/LauncherModel.java b/src/com/android/launcher3/LauncherModel.java
index afd5330..e1cd298 100644
--- a/src/com/android/launcher3/LauncherModel.java
+++ b/src/com/android/launcher3/LauncherModel.java
@@ -2387,7 +2387,7 @@
             Collections.sort(allWorkspaceItems, new Comparator<ItemInfo>() {
                 @Override
                 public int compare(ItemInfo lhs, ItemInfo rhs) {
-                    return (int) (lhs.container - rhs.container);
+                    return Long.compare(lhs.container, rhs.container);
                 }
             });
             for (ItemInfo info : allWorkspaceItems) {