[clang] [clang] [NFC] explicitly check if ParentMap contains key (PR #121736)

[Jay Foad via cfe-commits]

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@@ -34,13 +34,13 @@ static void BuildParentMap(MapTy& M, Stmt* S,
   case Stmt::PseudoObjectExprClass: {
     PseudoObjectExpr *POE = cast<PseudoObjectExpr>(S);
 
-    if (OVMode == OV_Opaque && M[POE->getSyntacticForm()])
+    if (OVMode == OV_Opaque && M.contains(POE->getSyntacticForm()))
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jayfoad wrote:

Could put this and the next `if` inside one big `if (M.contains)` check to avoid a duplicated map lookup.

https://github.com/llvm/llvm-project/pull/121736