[clang] [Serialization] Load Specializations Lazily (1/2) (PR #76774)

[Vassil Vassilev via cfe-commits]

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@@ -150,6 +150,11 @@ class ExternalASTSource : public RefCountedBase<ExternalASTSource> {
   virtual bool
   FindExternalVisibleDeclsByName(const DeclContext *DC, DeclarationName Name);
 
+  /// Load all the external specialzations for the Decl and the corresponding
+  /// template arguments.
+  virtual void LoadExternalSpecs(const Decl *D,
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vgvassilev wrote:

```suggestion
  virtual void FindExternalSpecialization(const Decl *D,
```
sounds more consistent to the surroundings here.


https://github.com/llvm/llvm-project/pull/76774