Version bump, make it so that invalidating the data set preserves scroll location

astrid/AndroidManifest.xml

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
           package="com.timsu.astrid"
-          android:versionName="3.3.0 (bug fix release)" 
-          android:versionCode="155">
+          android:versionName="3.3.1 (bug fix release)" 
+          android:versionCode="156">
           
   <!-- widgets, alarms, and services will break if Astrid is installed on SD card -->
   <!--    android:installLocation="internalOnly"> -->

astrid/src/com/todoroo/astrid/adapter/TaskAdapter.java

@@ -737,7 +737,14 @@ public class TaskAdapter extends CursorAdapter implements Filterable {
     public void notifyDataSetChanged() {
         super.notifyDataSetChanged();
         fontSize = Preferences.getIntegerFromString(R.string.p_fontSize, 20);
+    }
 
+    @Override
+    public void notifyDataSetInvalidated() {
+        ListView view = activity.getListView();
+        int scroll = view.getScrollY();
+        super.notifyDataSetInvalidated();
+        view.scrollTo(0, scroll);
     }
 
     private final View.OnClickListener completeBoxListener = new View.OnClickListener() {