[ubsan] Extend the nonnull arg check to ObjC

UBSan's nonnull argument check applies when a parameter has the
"nonnull" attribute. The check currently works for FunctionDecls, but
not for ObjCMethodDecls. This patch extends the check to work for ObjC.

Differential Revision: https://reviews.llvm.org/D30599

llvm-svn: 296996
diff --git a/clang/lib/CodeGen/CGObjC.cpp b/clang/lib/CodeGen/CGObjC.cpp
index adeb6d1..a67131a 100644
--- a/clang/lib/CodeGen/CGObjC.cpp
+++ b/clang/lib/CodeGen/CGObjC.cpp
@@ -427,7 +427,7 @@
   QualType ResultType = method ? method->getReturnType() : E->getType();
 
   CallArgList Args;
-  EmitCallArgs(Args, method, E->arguments());
+  EmitCallArgs(Args, method, E->arguments(), /*AC*/AbstractCallee(method));
 
   // For delegate init calls in ARC, do an unsafe store of null into
   // self.  This represents the call taking direct ownership of that