Fix DXVA status for some decoders after 4a79186.

Checking status only once is not reliable.
Even LAV Video Decoder can disable HW decoding on fly except DXVA Native mode.

Fixes #3881
Show tooltip with HW decoder name in status bar.

Fixes #3873
Statusbar: fix some visual glitches
VideoRenderers: remove asserts from 8d2b621

WM_SIZE messages may be lagging behind