Imports of loopclosure command

PathSynopsis
golang.org/x/tools/go/analysis/passes/loopclosurePackage loopclosure defines an Analyzer that checks for references to enclosing loop variables from within nested functions.
golang.org/x/tools/go/analysis/singlecheckerPackage singlechecker defines the main function for an analysis driver with only a single analysis.
golang.org/x/tools/internal/analysisinternalPackage analysisinternal provides gopls' internal analyses with a number of helper functions that operate on typed syntax trees.