Revert "[ObjC] Emit class msgSend stub calls (#183923)"
This reverts commit 077991463253b9295f291d4e4d2078521e518717.
Need to revert this follow up commit to 6758becb8f19593f5341b2e4d575dbf411ad706e
in order to revert an earlier commit which caused 2 test failures on a bot.
