Fix leak of GlobalModuleIndex::IdentifierIndex, found by LSan.

llvm-svn: 207262
diff --git a/clang/lib/Serialization/GlobalModuleIndex.cpp b/clang/lib/Serialization/GlobalModuleIndex.cpp
index 21a7149..04e4fb2 100644
--- a/clang/lib/Serialization/GlobalModuleIndex.cpp
+++ b/clang/lib/Serialization/GlobalModuleIndex.cpp
@@ -228,7 +228,9 @@
   }
 }
 
-GlobalModuleIndex::~GlobalModuleIndex() { }
+GlobalModuleIndex::~GlobalModuleIndex() {
+  delete static_cast<IdentifierIndexTable *>(IdentifierIndex);
+}
 
 std::pair<GlobalModuleIndex *, GlobalModuleIndex::ErrorCode>
 GlobalModuleIndex::readIndex(StringRef Path) {