[clang-tools-extra] Add support for renaming objc methods, even those with multiple selector pieces (PR #76466)

[kadir çetinkaya via cfe-commits]

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@@ -38,6 +38,11 @@
 
 namespace clang {
 namespace clangd {
+
+std::vector<SymbolRange> collectRenameIdentifierRanges(
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kadircet wrote:

let's move this into anonymous namespace, and add some comments explaining what it does?

https://github.com/llvm/llvm-project/pull/76466