[gn build] Port 6aabf60

Author: llvmgnsyncbot

llvm/utils/gn/secondary/clang-tools-extra/clangd/BUILD.gn

@@ -132,7 +132,6 @@ static_library("clangd") {
     "index/Ref.cpp",
     "index/Relation.cpp",
     "index/Serialization.cpp",
-    "index/StdLib.cpp",
     "index/Symbol.cpp",
     "index/SymbolCollector.cpp",
     "index/SymbolID.cpp",

llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn

@@ -99,7 +99,6 @@ unittest("ClangdTests") {
     "SemanticSelectionTests.cpp",
     "SerializationTests.cpp",
     "SourceCodeTests.cpp",
-    "StdLibTests.cpp",
     "SymbolCollectorTests.cpp",
     "SymbolInfoTests.cpp",
     "SyncAPI.cpp",