[clang] [clang] Fix -Wdouble-promotion in C++ list-initialization (PR #159992)

[via cfe-commits]

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@@ -12909,7 +12909,19 @@ static void AnalyzeImplicitConversions(
 
   // Skip past explicit casts.
   if (auto *CE = dyn_cast<ExplicitCastExpr>(E)) {
-    E = CE->getSubExpr()->IgnoreParenImpCasts();
+    E = CE->getSubExpr();
+    // In the special case of C++ function-style cast with braces,
+    // CXXFunctionalCastExpr has InitListExpr as direct child with a single
+    // initializer. This InitListExpr basically belongs to the cast itself, so
+    // we skip it too. Specifically this is needed to silence -Wdouble-promotion
----------------
Sirraide wrote:

```suggestion
    // In the special case of a C++ function-style cast with braces,
    // CXXFunctionalCastExpr has an InitListExpr as direct child with a single
    // initializer. This InitListExpr basically belongs to the cast itself, so
    // we skip it too. Specifically this is needed to silence -Wdouble-promotion
```
nit

https://github.com/llvm/llvm-project/pull/159992