Revert "Update to LLVM's use of WeakTrackingVH; NFC"

This reverts commit r301427.

llvm-svn: 301430
diff --git a/clang/lib/CodeGen/CGDeclCXX.cpp b/clang/lib/CodeGen/CGDeclCXX.cpp
index ff766e6..f61d60a 100644
--- a/clang/lib/CodeGen/CGDeclCXX.cpp
+++ b/clang/lib/CodeGen/CGDeclCXX.cpp
@@ -571,10 +571,9 @@
   FinishFunction();
 }
 
-void CodeGenFunction::GenerateCXXGlobalDtorsFunc(
-    llvm::Function *Fn,
-    const std::vector<std::pair<llvm::WeakTrackingVH, llvm::Constant *>>
-        &DtorsAndObjects) {
+void CodeGenFunction::GenerateCXXGlobalDtorsFunc(llvm::Function *Fn,
+                  const std::vector<std::pair<llvm::WeakVH, llvm::Constant*> >
+                                                &DtorsAndObjects) {
   {
     auto NL = ApplyDebugLocation::CreateEmpty(*this);
     StartFunction(GlobalDecl(), getContext().VoidTy, Fn,