Fetch the wallpaper category from the server instead of cache when launching the app(activity).

Bug: 169029398
Change-Id: I0549b2213a2567a7a46a79f0a779f08c61d0b163
diff --git a/src/com/android/customization/picker/CustomizationPickerActivity.java b/src/com/android/customization/picker/CustomizationPickerActivity.java
index 86845fc..786bebd 100644
--- a/src/com/android/customization/picker/CustomizationPickerActivity.java
+++ b/src/com/android/customization/picker/CustomizationPickerActivity.java
@@ -124,6 +124,8 @@
             return;
         }
 
+        mDelegate.getCategoryProvider().resetIfNeeded();
+
         setContentView(R.layout.activity_customization_picker_main);
         setUpBottomNavView();
         mBottomActionBar = findViewById(R.id.bottom_actionbar);