[llvm] [LLVM] Create `lf_alias` nodes for `typedef` and `using` (PR #153936)

[Alexandre Ganea via llvm-commits]

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@@ -952,6 +952,19 @@ class EndPrecompRecord : public TypeRecord {
   uint32_t Signature = 0;
 };
 
+// LF_ALIAS
+class AliasRecord : public TypeRecord {
+public:
+  AliasRecord() = default;
+  explicit AliasRecord(TypeRecordKind Kind) : TypeRecord(Kind) {}
+  AliasRecord(TypeIndex UnderlyingType, StringRef Name)
+      : TypeRecord(TypeRecordKind::Alias), UnderlyingType(UnderlyingType), Name(Name) {}
+
+  TypeIndex UnderlyingType;
+  StringRef Name;
+
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aganea wrote:

Remove extra blank line

https://github.com/llvm/llvm-project/pull/153936