[clang] [clang-tools-extra] [clangd] Autocomplete fixes for methods (PR #165916)

[Nathan Ridge via cfe-commits]

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@@ -6860,12 +6966,19 @@ void SemaCodeCompletion::CodeCompleteQualifiedId(Scope *S, CXXScopeSpec &SS,
   // resolves to a dependent record.
   DeclContext *Ctx = SemaRef.computeDeclContext(SS, /*EnteringContext=*/true);
 
+  std::optional<Sema::ContextRAII> SavedContext;
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HighCommander4 wrote:

nit: `SimulatedContext` may be a more descriptive name for this

https://github.com/llvm/llvm-project/pull/165916