Revert "Write export image to a temp file then rename."

This reverts commit e7a4315c2f9f901ce6da8f3d4209a645096d2274.
Revert "Return a Bitmap from ExportAsImage"

This reverts commit 95899f1650092dce44fc8719b33f1d4ca22097d0.
Revert "ExportAsImage to export only one view at higher resolution."

This reverts commit 75e38044f8b922aac46142fb46f3a325b58a6f03.