[clang-tools-extra] [clangd] Add designator hints for parenthesis aggregate initialization (PR #170642)

[Mythreya Kuricheti via cfe-commits]

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@@ -1746,6 +1732,19 @@ TEST(TypeHints, SubstTemplateParameterAliases) {
 }
 
 TEST(DesignatorHints, Basic) {
+  assertDesignatorHints(R"cpp(
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MythreyaK wrote:

I think my testing code slipped in, reverted it, thanks! 

https://github.com/llvm/llvm-project/pull/170642