Silence static analyzer getAs<RecordType> null dereference warnings. NFCI.

The static analyzer is warning about potential null dereferences, but in these cases we should be able to use castAs<RecordType> directly and if not assert will fire for us.

llvm-svn: 373584
diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index 31cf2ae..5e51f2e 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -659,7 +659,7 @@
 }
 
 bool ConstStructBuilder::Build(InitListExpr *ILE, bool AllowOverwrite) {
-  RecordDecl *RD = ILE->getType()->getAs<RecordType>()->getDecl();
+  RecordDecl *RD = ILE->getType()->castAs<RecordType>()->getDecl();
   const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
 
   unsigned FieldNo = -1;
@@ -839,7 +839,7 @@
 }
 
 llvm::Constant *ConstStructBuilder::Finalize(QualType Type) {
-  RecordDecl *RD = Type->getAs<RecordType>()->getDecl();
+  RecordDecl *RD = Type->castAs<RecordType>()->getDecl();
   llvm::Type *ValTy = CGM.getTypes().ConvertType(Type);
   return Builder.build(ValTy, RD->hasFlexibleArrayMember());
 }