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

Getting a weird buildbot failure that I need to investigate.

llvm-svn: 215870
diff --git a/llvm/lib/Transforms/IPO/StripSymbols.cpp b/llvm/lib/Transforms/IPO/StripSymbols.cpp
index 813f30d..1abbccc 100644
--- a/llvm/lib/Transforms/IPO/StripSymbols.cpp
+++ b/llvm/lib/Transforms/IPO/StripSymbols.cpp
@@ -191,7 +191,7 @@
 
 /// Find values that are marked as llvm.used.
 static void findUsedValues(GlobalVariable *LLVMUsed,
-                           SmallPtrSetImpl<const GlobalValue*> &UsedValues) {
+                           SmallPtrSet<const GlobalValue*, 8> &UsedValues) {
   if (!LLVMUsed) return;
   UsedValues.insert(LLVMUsed);