[clang] [Clang] Make the result type of sizeof/pointer subtraction/size_t literals be typedefs instead of built-in types (PR #143653)

[Matheus Izvekov via cfe-commits]

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@@ -1961,11 +1969,20 @@ class ASTContext : public RefCountedBase<ASTContext> {
   /// <stddef.h>.
   ///
   /// The sizeof operator requires this (C99 6.5.3.4p4).
-  CanQualType getSizeType() const;
+  QualType getSizeType() const;
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mizvekov wrote:

Can you provide `CanQualType getCanonicalFoo` versions of these, instead of sprinkling `->getCanonicalUnqualifiedType` all around?

https://github.com/llvm/llvm-project/pull/143653