[gn build] Port cc380f6e9ba4
diff --git a/llvm/utils/gn/secondary/lldb/source/Plugins/Language/CPlusPlus/BUILD.gn b/llvm/utils/gn/secondary/lldb/source/Plugins/Language/CPlusPlus/BUILD.gn
index 7ea5f8c..9c33b31 100644
--- a/llvm/utils/gn/secondary/lldb/source/Plugins/Language/CPlusPlus/BUILD.gn
+++ b/llvm/utils/gn/secondary/lldb/source/Plugins/Language/CPlusPlus/BUILD.gn
@@ -64,6 +64,7 @@
     "MsvcStl.cpp",
     "MsvcStlAtomic.cpp",
     "MsvcStlSmartPointer.cpp",
+    "MsvcStlTree.cpp",
     "MsvcStlTuple.cpp",
     "MsvcStlUnordered.cpp",
     "MsvcStlVariant.cpp",