Update aosp/master LLVM for rebase to r222494.

Change-Id: Ic787f5e0124df789bd26f3f24680f45e678eef2d
diff --git a/lib/CodeGen/GCMetadata.cpp b/lib/CodeGen/GCMetadata.cpp
index c3e4f3e..ed40982 100644
--- a/lib/CodeGen/GCMetadata.cpp
+++ b/lib/CodeGen/GCMetadata.cpp
@@ -73,7 +73,7 @@
       std::unique_ptr<GCStrategy> S = I->instantiate();
       S->M = M;
       S->Name = Name;
-      StrategyMap.GetOrCreateValue(Name).setValue(S.get());
+      StrategyMap[Name] = S.get();
       StrategyList.push_back(std::move(S));
       return StrategyList.back().get();
     }