Updating drop button targets

> Splitting DeleteDropTarget into delete and uninstall
> Showing UninstallDropTarget for app shortcuts on workspace
> Showing InfoDropTarget only when developer options is enabled

Change-Id: I4396571d2199d1581bb9c733aef88ab9b0ebd79d

src/com/android/launcher3/DropTarget.java

@@ -139,7 +139,7 @@ public interface DropTarget {
 
     /**
      * Handle an object being dropped on the DropTarget
-     * 
+     *
      * @param source DragSource where the drag started
      * @param x X coordinate of the drop location
      * @param y Y coordinate of the drop location
@@ -169,7 +169,7 @@ public interface DropTarget {
     /**
      * Check if a drop action can occur at, or near, the requested location.
      * This will be called just before onDrop.
-     * 
+     *
      * @param source DragSource where the drag started
      * @param x X coordinate of the drop location
      * @param y Y coordinate of the drop location