[clang] Check the type of Objective-C++ instance variables in WebKit member variable checkers. (PR #127570)

[Ryosuke Niwa via cfe-commits]

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@@ -87,6 +92,31 @@ class RawPtrRefMemberChecker
     }
   }
 
+  void visitObjCDecl(const ObjCContainerDecl *CD) const {
+    if (auto *ID = dyn_cast<ObjCInterfaceDecl>(CD)) {
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rniwa wrote:

I don't think so. `ObjCContainerDecl` could be `ObjCCategoryDecl` or `ObjCProtocolDecl` as well.
Or are you saying CD could be null?

https://github.com/llvm/llvm-project/pull/127570