[clang] [Clang] Disallow explicit object parameters in more contexts (PR #89078)

[Aaron Ballman via cfe-commits]

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@@ -7525,6 +7525,8 @@ def err_explicit_object_parameter_mutable: Error<
 def err_invalid_explicit_object_type_in_lambda: Error<
   "invalid explicit object parameter type %0 in lambda with capture; "
   "the type must be the same as, or derived from, the lambda">;
+def err_explicit_object_parameter_invalid: Error<
+  "an explicit object parameter is not allowed here">;
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AaronBallman wrote:

"here" is pretty ambiguous. Any chance we can reuse the `an explicit object parameter cannot appear in a non-member function` diagnostic, add a `%select` to it, and give specific names for what "here" is?

https://github.com/llvm/llvm-project/pull/89078