Revert "Revert "Synchronizing loader preload to avoid launcher getting stuck in loading state,""

This reverts commit 73aa3025c0001e58c57d009053dee03c0108ca3e.

Reason for revert: Post-drop revert

Change-Id: Ife752d26e07d9c064c938ff8d33d40457b54217a
diff --git a/src/com/android/launcher3/LauncherModel.java b/src/com/android/launcher3/LauncherModel.java
index 929606e..a4d188f 100644
--- a/src/com/android/launcher3/LauncherModel.java
+++ b/src/com/android/launcher3/LauncherModel.java
@@ -493,6 +493,15 @@
         }
     }
 
+    public void startLoaderForResultsIfNotLoaded(LoaderResults results) {
+        synchronized (mLock) {
+            if (!isModelLoaded()) {
+                Log.d(TAG, "Workspace not loaded, loading now");
+                startLoaderForResults(results);
+            }
+        }
+    }
+
     /**
      * Loads the workspace screen ids in an ordered list.
      */