[PATCH 0/1] MR1239: winegstreamer: Pause streaming threads when seeking.

[Zhiyi Zhang (＠zhiyi)]

The streaming threads and GST_Seeking_SetPositions() contend for the same flushing locks.
GST_Seeking_SetPositions() needs to acquire all the flushing locks before doing the actual
stream seeking, having the streaming threads fighting for the same locks will make
GST_Seeking_SetPositions() wait for a unusually long time.

This reduces PowerPoint 2016 video seeking time from ~5s to almost an instant and fixes a regression
for Fallout 3.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=53403