[clang][deps] NFC: Replace a vector with an array

[davidstone]

Summary

ResourceDirectoryCache::findResourceDir uses a std::vector when a std::array would do. Make this replacement and declare the variable const.

clang/tools/clang-scan-deps/ClangScanDeps.cpp

StringRef findResourceDir(const tooling::CommandLineArguments &Args,
     const std::string &ClangBinaryName =
         std::string(llvm::sys::path::filename(ClangBinaryPath));
 
     std::unique_lock<std::mutex> LockGuard(CacheLock);
     const auto &CachedResourceDir = Cache.find(ClangBinaryPath);
     if (CachedResourceDir != Cache.end())
       return CachedResourceDir->second;
 
-    std::vector<StringRef> PrintResourceDirArgs{ClangBinaryName};
-    if (ClangCLMode)
-      PrintResourceDirArgs.push_back("/clang:-print-resource-dir");
-    else
-      PrintResourceDirArgs.push_back("-print-resource-dir");
+    const std::array<StringRef, 2> PrintResourceDirArgs{
+        ClangBinaryName,
+        ClangCLMode ? "/clang:-print-resource-dir" : "-print-resource-dir"};
 
     llvm::SmallString<64> OutputFile, ErrorFile;
     llvm::sys::fs::createTemporaryFile("print-resource-dir-output",
                                        "" /*no-suffix*/, OutputFile);
     llvm::sys::fs::createTemporaryFile("print-resource-dir-error",
                                        "" /*no-suffix*/, ErrorFile);
     llvm::FileRemover OutputRemover(OutputFile.c_str());
     llvm::FileRemover ErrorRemover(ErrorFile.c_str());