Fix another regression from the "skip vtable pointer initialization"
optimization. Make sure to require a vtable when trying to get the address
of a VTT, otherwise we would never end up emitting the VTT.

llvm-svn: 131400
diff --git a/clang/lib/CodeGen/CGVTT.cpp b/clang/lib/CodeGen/CGVTT.cpp
index a6849f8..aefc41e 100644
--- a/clang/lib/CodeGen/CGVTT.cpp
+++ b/clang/lib/CodeGen/CGVTT.cpp
@@ -411,6 +411,8 @@
   Out.flush();
   llvm::StringRef Name = OutName.str();
 
+  ComputeVTableRelatedInformation(RD, /*VTableRequired=*/true);
+
   VTTBuilder Builder(CGM, RD, /*GenerateDefinition=*/false);
 
   const llvm::Type *Int8PtrTy =