CondVar wait morhping has a special case for timed waits.
The code goes back to 2006, it seems that there might have
been some reasons to do this back then.
But now it does not seem to be necessary.
Wait morphing should work just fine after timed CondVar waits.
Remove the special case and simplify code.

PiperOrigin-RevId: 565798838
Change-Id: I4e4d61ae7ebd521f5c32dfc673e57a0c245e7cfb