Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.

llvm-svn: 215869
diff --git a/clang/lib/Serialization/ModuleManager.cpp b/clang/lib/Serialization/ModuleManager.cpp
index 2c10c11..8b0a4ed 100644
--- a/clang/lib/Serialization/ModuleManager.cpp
+++ b/clang/lib/Serialization/ModuleManager.cpp
@@ -249,7 +249,7 @@
 void
 ModuleManager::visit(bool (*Visitor)(ModuleFile &M, void *UserData),
                      void *UserData,
-                     llvm::SmallPtrSet<ModuleFile *, 4> *ModuleFilesHit) {
+                     llvm::SmallPtrSetImpl<ModuleFile *> *ModuleFilesHit) {
   // If the visitation order vector is the wrong size, recompute the order.
   if (VisitOrder.size() != Chain.size()) {
     unsigned N = size();