[clang] [clang][ssaf] Implement JSONFormat (PR #180021)

[Balázs Benics via cfe-commits]

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@@ -68,7 +76,7 @@ TUSummary MockSerializationFormat::readTUSummary(llvm::StringRef Path) {
     auto &Table = getIdTable(Summary);
 
     std::unique_ptr<EntitySummary> Result = InfoEntry.Deserialize(Repr, Table);
-    if (!Result) // TODO: Handle error.
+    if (!Result)
       continue;
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steakhal wrote:

I think we should create some StringError or something to return here. This isn't actually handled this way.

https://github.com/llvm/llvm-project/pull/180021