[clang] [Thread Safety Analysis] Fix a bug of context saving in alias-analysis (PR #178825)

[Marco Elver via cfe-commits]

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@@ -0,0 +1,36 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -Wthread-safety -Wthread-safety-pointer -Wthread-safety-beta %s
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melver wrote:

Not sure this requires C, but if not, could you please reconstruct this test case in the namespace CapabilityAliases in warn-thread-safety-analysis.cpp test.

https://github.com/llvm/llvm-project/pull/178825