[clangd] Use include_cleaner spelling strategies in clangd.

[VitaNuo]

Remove unrelated formatting.

[VitaNuo]

Duplicate of https://reviews.llvm.org/D152913. Landed the other one.

clang-tools-extra/clangd/Hover.cpp

 #include "Config.h"
 #include "FindTarget.h"
 #include "Headers.h"
 #include "IncludeCleaner.h"
 #include "ParsedAST.h"
 #include "Selection.h"
 #include "SourceCode.h"
 #include "clang-include-cleaner/Analysis.h"
+#include "clang-include-cleaner/IncludeSpeller.h"
 #include "clang-include-cleaner/Types.h"
 #include "index/SymbolCollector.h"
 #include "support/Logger.h"
 #include "support/Markup.h"
 #include "support/Trace.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTDiagnostic.h"
 #include "clang/AST/ASTTypeTraits.h"
void maybeAddSymbolProviders(ParsedAST &AST, HoverInfo &HI,
   // Pick the best-ranked non-#include'd provider
   const auto &H = RankedProviders.front();
   if (H.kind() == include_cleaner::Header::Physical &&
       H.physical() == SM.getFileEntryForID(SM.getMainFileID()))
     // Do not show main file as provider, otherwise we'll show provider info
     // on local variables, etc.
     return;
 
-  HI.Provider = spellHeader(AST, SM.getFileEntryForID(SM.getMainFileID()), H);
+  HI.Provider = include_cleaner::spellHeader(
+      {H, AST.getPreprocessor().getHeaderSearchInfo(),
+       SM.getFileEntryForID(SM.getMainFileID())});
 }
 
 // FIXME: similar functions are present in FindHeaders.cpp (symbolName)
 // and IncludeCleaner.cpp (getSymbolName). Introduce a name() method into
 // include_cleaner::Symbol instead.
 std::string getSymbolName(include_cleaner::Symbol Sym) {
   std::string Name;
   switch (Sym.kind()) {

clang-tools-extra/clangd/IncludeCleaner.h

 void setIncludeCleanerAnalyzesStdlib(bool B);
 
 /// Converts the clangd include representation to include-cleaner
 /// include representation.
 include_cleaner::Includes
 convertIncludes(const SourceManager &SM,
                 const llvm::ArrayRef<Inclusion> Includes);
 
-/// Determines the header spelling of an include-cleaner header
-/// representation. The spelling contains the ""<> characters.
-std::string spellHeader(ParsedAST &AST, const FileEntry *MainFile,
-                        include_cleaner::Header Provider);
-
 std::vector<include_cleaner::SymbolReference>
 collectMacroReferences(ParsedAST &AST);
 
 /// Find the first provider in the list that is matched by the includes.
 std::optional<include_cleaner::Header>
 firstMatchedProvider(const include_cleaner::Includes &Includes,
                      llvm::ArrayRef<include_cleaner::Header> Providers);
 } // namespace clangd
 } // namespace clang
 
 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_INCLUDECLEANER_H

clang-tools-extra/clangd/IncludeCleaner.cpp

llvm::StringRef ResolvedPath =
         getResolvedPath(SymbolWithMissingInclude.Providers.front());
     if (isFilteredByConfig(Cfg, ResolvedPath)) {
       dlog("IncludeCleaner: not diagnosing missing include {0}, filtered by "
            "config",
            ResolvedPath);
       continue;
     }
 
-    std::string Spelling =
-        spellHeader(AST, MainFile, SymbolWithMissingInclude.Providers.front());
+    std::string Spelling = include_cleaner::spellHeader(
+        {SymbolWithMissingInclude.Providers.front(),
+         AST.getPreprocessor().getHeaderSearchInfo(), MainFile});
 
     llvm::StringRef HeaderRef{Spelling};
     bool Angled = HeaderRef.starts_with("<");
     // We might suggest insertion of an existing include in edge cases, e.g.,
     // include is present in a PP-disabled region, or spelling of the header
     // turns out to be the same as one of the unresolved includes in the
     // main file.
     std::optional<tooling::Replacement> Replacement = HeaderIncludes.insert(
if (!FE) {
       continue;
     }
     TransformedInc.Resolved = *FE;
     ConvertedIncludes.add(std::move(TransformedInc));
   }
   return ConvertedIncludes;
 }
 
-std::string spellHeader(ParsedAST &AST, const FileEntry *MainFile,
-                        include_cleaner::Header Provider) {
-  if (Provider.kind() == include_cleaner::Header::Physical) {
-    if (auto CanonicalPath =
-            getCanonicalPath(Provider.physical()->getLastRef(),
-                             AST.getSourceManager().getFileManager())) {
-      std::string SpelledHeader =
-          llvm::cantFail(URI::includeSpelling(URI::create(*CanonicalPath)));
-      if (!SpelledHeader.empty())
-        return SpelledHeader;
-    }
-  }
-  return include_cleaner::spellHeader(
-      {Provider, AST.getPreprocessor().getHeaderSearchInfo(), MainFile});
-}
-
 std::vector<const Inclusion *>
 getUnused(ParsedAST &AST,
           const llvm::DenseSet<IncludeStructure::HeaderID> &ReferencedFiles,
           const llvm::StringSet<> &ReferencedPublicHeaders) {
   trace::Span Tracer("IncludeCleaner::getUnused");
   const Config &Cfg = Config::current();
   std::vector<const Inclusion *> Unused;
   for (const Inclusion &MFI : AST.getIncludeStructure().MainFileIncludes) {