Wait for iref box if the heic file has Exif data

When exif items are present, iref box must be present to
associate exif with image items.

bug: 123094535
test: use ExifInterface on files without grid, should be
      able to extract exif if available.

Change-Id: Ia0728cdeefe28318a4ca03193ad93c3b64d78f7a