Bug in current selection and Ifilter preview

[win32]

Halo,

I am on 1382a, for some builds now, one of the recent changes introduced the following bug.
Whenever I select a video file and the default windows inline/inpreview iflter video player shows up(with a play button), if I change the selection to another file the mini player stucks showing the same frame from the previous file.

I have to close the preview pane and open it again to show the current file.
(Also if it helps locating the bug, a bit strange is that if I hit the preview play button it playbacks the correct currently selected file, if I stop it, it displays the frame from the previous file.

[void]

Everything 1.5.0.1383a improves previews.

Everything will now forcefully enable preview_multiple_handler_instances when showing previews with the "Windows Media Player Rich Preview Handler".
( {031EE060-67BC-460d-8847-E4A7C5E45A27} )

This preview handler doesn't handle the Unload request correctly.
The issue is mitigated by using multiple instances.
This fix may cause issues if the "Windows Media Player Rich Preview Handler" is ever fixed (It has been broken since Windows 10)



1383a fixes an issue with preview_release_handler_on_clear
Previous versions would unload the handler immediately after the preview was shown.



Preview handlers are now called in exactly the same way as Windows Explorer:
SetSite
Initialize
SetWindow
DoPreview
SetRect
...
Unload
...
(repeat from start)
...
Release (when the preview pane is closed)



1383a fixes an issue with starting a OLE drag drop operation and showing a preview at the same time.
The drag operation would not start at all in previous versions.

[win32]

Fix confirmed. Thank you for all your work!