[clang-tools-extra] Symbol tags in SymbolInformation, WorkspaceSymbol, CallHierarchyItem and TypeHierarchyItem (PR #170103)

[Dimitri Ratz via cfe-commits]

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@@ -208,21 +266,103 @@ SymbolTags computeSymbolTags(const NamedDecl &ND) {
   return Result;
 }
 
+// Filter symbol tags based on the presence of other tags and the kind of
+// symbol. This is needed to avoid redundant tags.
+SymbolTags filterSymbolTags(const NamedDecl &ND, const SymbolTags ST) {
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ratzdi wrote:

It is not always advisable to pass on the calculated symbol tags directly. For example, `void foo() final {}` would have, among others, the tags `virtual` and `overrides`. These two can be correctly reduced to a single symbol tag.

https://github.com/llvm/llvm-project/pull/170103