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

[Nathan Ridge via cfe-commits]

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@@ -1822,6 +1821,63 @@ TEST(DesignatorHints, NoCrash) {
                         ExpectedHint{".b=", "b"});
 }
 
+TEST(DesignatorHints, BasicParenInit) {
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HighCommander4 wrote:

(I edited the PR to make this change to `ParenInitTemplate` as well.)

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