[clang] [cindex] Add API to query the class methods of a type (PR #123539)

[Aaron Ballman via cfe-commits]

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@@ -54,6 +54,33 @@ unsigned clang_visitCXXBaseClasses(CXType PT, CXFieldVisitor visitor,
   return true;
 }
 
+unsigned clang_visitCXXMethods(CXType PT, CXFieldVisitor visitor,
+                               CXClientData client_data) {
+  CXCursor PC = clang_getTypeDeclaration(PT);
+  if (clang_isInvalid(PC.kind))
+    return false;
+  const CXXRecordDecl *RD =
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AaronBallman wrote:

```suggestion
  const auto *RD =
```

https://github.com/llvm/llvm-project/pull/123539