Bug 1021290. More Atomics.h build fixes for clang-cl. r=froydnj

This is basically more of bug 932454

--HG--
extra : rebase_source : 0f9a5d43164efb6940d17e406f41691cb3d26435

mfbt/Atomics.h

@@ -866,6 +866,7 @@ template<typename T>
 struct IntrinsicAddSub<T*> : public IntrinsicApplyHelper<T*>
 {
   typedef typename IntrinsicApplyHelper<T*>::ValueType ValueType;
+  typedef typename IntrinsicBase<T>::Primitives Primitives;
 
   static ValueType add(ValueType& aPtr, ptrdiff_t aAmount)
   {
@@ -893,6 +894,7 @@ struct AtomicIntrinsics : public IntrinsicMemoryOps<T, Order>,
                           public IntrinsicIncDec<T>
 {
   typedef typename IntrinsicIncDec<T>::ValueType ValueType;
+  typedef typename IntrinsicBase<T>::Primitives Primitives;
 
   static ValueType or_(ValueType& aPtr, T aVal)
   {