[clang] [alpha.webkit.NoUnretainedMemberChecker] Recognize NS_REQUIRES_PROPERTY_DEFINITIONS (PR #141293)

[Ziqing Luo via cfe-commits]

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@@ -174,7 +175,15 @@ class RawPtrRefMemberChecker
     if (!PropType)
       return;
 
-    auto IsUnsafePtr = isUnsafePtr(QT);
+    if (const ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(CD)) {
+      if (!RTC || !RTC->defaultSynthProperties() ||
+          ID->isObjCRequiresPropertyDefs())
+        return;
+    }
+
+    bool ignoreARC =
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ziqingluo-90 wrote:

As a reader unfamiliar with the checker, I'd appreciate some comments on `ignoreARC`.  Specifically, 1) why to `ignoreARC` for non-read-only and `assign` `PD`s; and 2) does `ignoreARC` make it "more likely" an unsafe ptr?

https://github.com/llvm/llvm-project/pull/141293