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When transparency is present, it's not enough to just write 32bpp samples.
One need to use the full BITMAPV3INFOHEADER syntax and specify the
masks for BGRA.
see https://en.wikipedia.org/wiki/BMP_file_format#Pixel_storage
Also remove the height-flip trick and write samples bottom-to-top instead.
Change-Id: If5d92c11453b96764b5bfbf19e9678e632bc911f
(cherry picked from commit 480cd51de6
)