am 9c891ca3: am 2a55b596: Merge "libvideoeditor: fix cannot show some thumbnails in storyboard or no frame display in PreviewRenderer surface after importing video"

* commit '9c891ca36a7f2acecd70d41ff39a2025048bb0b1':
  libvideoeditor: fix cannot show some thumbnails in storyboard or no frame display in PreviewRenderer surface after importing video