Backport of "gstgiobasesink: Handle incomplete writes in gst_gio_base_sink_render()" into 1.18
Backport of !1100 (merged) "gstgiobasesink: Handle incomplete writes in gst_gio_base_sink_render()".
Commits:
- 1a1a885d gstgiobasesink: Handle incomplete writes in gst_gio_base_sink_render()