[Bug 51788] windowscodecs:wmpformat test_decode() fails randomly

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51788

--- Comment #7 from Esme Povirk  ---
Never mind, changing the one heap allocation in wmp_decoder_copy_pixels to use
HEAP_ZERO_MEMORY fixes it.

Looking at jxrlib example code, that doesn't seem to be intended, but I really
don't want to dive into that mess and find the real problem. Hopefully failing
to write over parts of the user buffer in cases where a channel is 0 is the
only memory error, and zeroing that will get us consistency.