[clang-tools-extra] [clangd] Use `SymbolName` to represent Objective-C selectors (PR #82061)

[Alex Hoppen via cfe-commits]

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@@ -35,6 +35,49 @@ struct RenameOptions {
   bool RenameVirtual = true;
 };
 
+/// A name of a symbol that should be renamed.
+///
+/// Symbol's name can be composed of multiple strings. For example, Objective-C
+/// methods can contain multiple argument labels:
+///
+/// \code
+/// - (void) myMethodNamePiece: (int)x anotherNamePieces:(int)y;
+/// //       ^~ string 0 ~~~~~         ^~ string 1 ~~~~~
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ahoppen wrote:

Updated. Could you merge the change when CI has passed?

https://github.com/llvm/llvm-project/pull/82061