[clang] Respect the [[clang::unsafe_buffer_usage]] attribute for constructors (PR #91777)

[Dana Jansens via cfe-commits]

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@@ -1315,9 +1374,9 @@ class DerefSimplePtrArithFixableGadget : public FixableGadget {
 
   virtual std::optional<FixItList>
   getFixits(const FixitStrategy &s) const final;
-
-  // TODO remove this method from FixableGadget interface
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danakj wrote:

This one used to return null, but it does return something useful now. So instead of putting this TODO back (and equally putting it on every FixableGadget subclass), I can apply it up in the Gadget class.

https://github.com/llvm/llvm-project/pull/91777