[clang] [Clang] Implement diagnostics for why is_empty is false (PR #145044)

[Corentin Jabot via cfe-commits]

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@@ -1787,6 +1788,10 @@ def note_unsatisfied_trait_reason
            "%NonReplaceableField{has a non-replaceable member %1 of type %2}|"
            "%NTCBase{has a non-trivially-copyable base %1}|"
            "%NTCField{has a non-trivially-copyable member %1 of type %2}|"
+           "%NonEmptyMember{has a non-static data member %1 of type %2}|"
+           "%VirtualFunction{has a virtual function %1}|"
+           "%NonEmptyBase{has a base class %1 that is not empty}|"
+           "%ZeroLengthField{field %1 is a non-zero-length bit-field}|"
----------------
cor3ntin wrote:

```suggestion
           "%NonZeroLengthField{field %1 is a non-zero-length bit-field}|"
```

https://github.com/llvm/llvm-project/pull/145044