Subzero: Add -Wshadow to the build.

src/IceThreading.h

Index: src/IceThreading.h
diff --git a/src/IceThreading.h b/src/IceThreading.h
index 4f04935a1f2b188bbc03858b248f8f3bf7617e88..446d30375fb90297f5fda545eed6ba4a164ca1a9 100644
--- a/src/IceThreading.h
+++ b/src/IceThreading.h
@@ -54,8 +54,9 @@ class BoundedProducerConsumerQueue {
   operator=(const BoundedProducerConsumerQueue &) = delete;
 
 public:
-  BoundedProducerConsumerQueue(bool Sequential, size_t MaxSize = MaxStaticSize)
-      : MaxSize(std::min(MaxSize, MaxStaticSize)), Sequential(Sequential) {}
+  BoundedProducerConsumerQueue(bool MySequential,
+                               size_t MyMaxSize = MaxStaticSize)
+      : MaxSize(std::min(MyMaxSize, MaxStaticSize)), Sequential(MySequential) {}
   void blockingPush(T *Item) {
     {
       std::unique_lock<GlobalLockType> L(Lock);