Fix memory leak found by Sam Bishop: delete WList in the dstor of GRCoreEngineImpl.

llvm-svn: 54714
diff --git a/clang/lib/Analysis/GRCoreEngine.cpp b/clang/lib/Analysis/GRCoreEngine.cpp
index 548c4bf..1c64c28 100644
--- a/clang/lib/Analysis/GRCoreEngine.cpp
+++ b/clang/lib/Analysis/GRCoreEngine.cpp
@@ -156,6 +156,9 @@
     HandleBlockExit(L.getBlock(), Pred);
 }
 
+GRCoreEngineImpl::~GRCoreEngineImpl() {
+  delete WList;
+}
 
 void GRCoreEngineImpl::HandleBlockExit(CFGBlock * B, ExplodedNodeImpl* Pred) {