[clang] Fix WebKit static analyzers to support ref and deref methods to be defined on different classes. (PR #69985)

[Artem Dergachev via cfe-commits]

================
@@ -77,14 +77,53 @@ class RefCntblBaseVirtualDtorChecker
               (AccSpec == AS_none && RD->isClass()))
             return false;
 
-          std::optional<const CXXRecordDecl*> RefCntblBaseRD = isRefCountable(Base);
-          if (!RefCntblBaseRD || !(*RefCntblBaseRD))
+          auto hasRefInBase = clang::hasPublicMethodInBase(Base, "ref");
+          auto hasDerefInBase = clang::hasPublicMethodInBase(Base, "deref");
+
+          bool hasRef = hasRefInBase && *hasRefInBase != nullptr;
+          bool hasDeref = hasDerefInBase && *hasDerefInBase != nullptr;
+
+          const Type *T = Base->getType().getTypePtrOrNull();
+          if (!T)
+            return false;
+
+          const CXXRecordDecl *C = T->getAsCXXRecordDecl();
----------------
haoNoQ wrote:

`.getTypePtrOrNull()` is typically unnecessary, most of the code can use the overloaded `QualType::operator->()` to access the underlying `Type`:

        QualType T = Base->getType();
        if (T.isNull())
          return false;

        const CXXRecordDecl *C = T->getAsCXXRecordDecl();

etc.

https://github.com/llvm/llvm-project/pull/69985