Surface::makeImageSnapshot crashes if _nMakeImageSnapshotR returns null

[Sm0keySa1m0n]

Surface::makeImageSnapshot is correctly marked as @Nullable because _nMakeImageSnapshotR can return a null pointer. However, it doesn't check whether _nMakeImageSnapshotR returns null and instead always calls the Image constructor which will crash if the pointer is null.

[tonsky]

Thanks!