[clang-tools-extra] [clangd] Allow specifying what headers are always included via "" or <> (PR #67749)

[Sam McCall via cfe-commits]

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@@ -296,6 +296,19 @@ struct Fragment {
     // ::). All nested namespaces are affected as well.
     // Affects availability of the AddUsing tweak.
     std::vector<Located<std::string>> FullyQualifiedNamespaces;
+
+    /// List of regexes for headers that should always be included with a
+    /// ""-style include. By default, and in case of a conflict with
+    /// AngledHeaders (i.e. a header matches a regex in both QuotedHeaders and
+    /// AngledHeaders), system headers use <> and non-system headers use "".
+    /// These can match any suffix of the header file in question.
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sam-mccall wrote:

This should mention whether we're matching against the path to the header, or its spelling.

https://github.com/llvm/llvm-project/pull/67749