[Verifier] Don't abort on invalid cleanuprets

Code in visitEHPadPredecessors assume a little too much about the
validity of a cleanupret with an invalid cleanuppad operand.

llvm-svn: 262364
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index bea9b34..48792fb 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -3055,7 +3055,7 @@
       else
         FromPad = ConstantTokenNone::get(II->getContext());
     } else if (auto *CRI = dyn_cast<CleanupReturnInst>(TI)) {
-      FromPad = CRI->getCleanupPad();
+      FromPad = CRI->getOperand(0);
       Assert(FromPad != ToPadParent, "A cleanupret must exit its cleanup", CRI);
     } else if (auto *CSI = dyn_cast<CatchSwitchInst>(TI)) {
       FromPad = CSI;