[NFC] Fix downstream test failures due to new "dead_on_return" annotations and AST type sugaring. (#31466)
Following commit 9e0c06d (Set dead_on_return when passing arguments
indirectly), the "dead_on_return" annotation is now set on indirectly
passed arguments.
Following commit 7c402b8 (Reland [Clang] Make the SizeType,
SignedSizeType and PtrdiffType be named sugar types), the use of
some type aliases is more often preserved in AST dumps.