title: BitmapFactory.decodeFile returns null even image exists
body: <p>Saving the file:</p>
  
  <pre><code>FileOutputStream fo = null; 
  try { 
          fo = this.openFileOutput("test.png", Context.MODE_WORLD_READABLE); 
  } catch (FileNotFoundException e) { 
          e.printStackTrace(); 
  } 
  bitmap.compress(CompressFormat.PNG, 100, fo)
  </code></pre>
  
  <p>Loading the file:</p>
  
  <pre><code>String fname = this.getFilesDir().getAbsolutePath()+"/test.png"; 
  Bitmap bMap = BitmapFactory.decodeFile(fname);
  i.setImageBitmap(bMap);
  </code></pre>
  
  <p>The last line gives a null pointer exception, why is BitmapFactory.decodeFile returning null? I can verify that the file is getting saved correctly as I can pull it using adb and see the png displaying properly.</p>