[clang] [clang-tools-extra] [clang] Make `InitListExpr::isExplicit()` work (PR #195175)

[Aaron Ballman via cfe-commits]

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@@ -8144,7 +8144,7 @@ AST_MATCHER(CXXConstructorDecl, isDelegatingConstructor) {
 /// cxxDeductionGuideDecl(isExplicit()) will match #6, but not #5.
 AST_POLYMORPHIC_MATCHER(isExplicit, AST_POLYMORPHIC_SUPPORTED_TYPES(
                                         CXXConstructorDecl, CXXConversionDecl,
-                                        CXXDeductionGuideDecl)) {
+                                        CXXDeductionGuideDecl, InitListExpr)) {
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AaronBallman wrote:

We already have an `isImplicit` matcher for nodes which are implicitly added by the compiler like implicitly declared copy constructors, which does seem like a closer fit.

https://github.com/llvm/llvm-project/pull/195175