Delete the new visitor if an old one already exists.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99114 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/BugReporter.cpp b/lib/Checker/BugReporter.cpp
index d4b1502..7272b34 100644
--- a/lib/Checker/BugReporter.cpp
+++ b/lib/Checker/BugReporter.cpp
@@ -44,8 +44,10 @@
   visitor->Profile(ID);
   void *InsertPos;
 
-  if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos))
+  if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos)) {
+    delete visitor;
     return;
+  }
 
   CallbacksSet.InsertNode(visitor, InsertPos);
   Callbacks = F.Add(visitor, Callbacks);