go.tools/go/*: fix breakage caused by removal of types.NewPackage parameter.

(This fixes the build, but one test is failing.)

TBR=gri
R=gri
CC=golang-codereviews
https://golang.org/cl/66730043

go/gccgoimporter/parser.go

@@ -157,7 +157,7 @@ func (p *parser) getPkg(pkgpath, name string) *types.Package {
 	}
 	pkg := p.imports[pkgpath]
 	if pkg == nil && name != "" {
-		pkg = types.NewPackage(pkgpath, name, types.NewScope(nil))
+		pkg = types.NewPackage(pkgpath, name)
 		p.imports[pkgpath] = pkg
 	}
 	return pkg

go/importer/import.go

@@ -93,7 +93,7 @@ func (p *importer) pkg() *types.Package {
 	// if the package was imported before, use that one; otherwise create a new one
 	pkg := p.imports[path]
 	if pkg == nil {
-		pkg = types.NewPackage(path, name, types.NewScope(nil))
+		pkg = types.NewPackage(path, name)
 		p.imports[path] = pkg
 	}
 	p.pkgList = append(p.pkgList, pkg)