[clang] SSAF JSON Format (PR #180021)

[Aviral Goel via cfe-commits]

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@@ -21,6 +21,8 @@ namespace clang::ssaf {
 /// The table maps each unique EntityName to exactly one EntityId.
 /// Entities are never removed.
 class EntityIdTable {
+  friend class SerializationFormat;
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aviralg wrote:

For serializing and deserializing `EntityIdTable` objects.

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