Add validation infrastructure for "pub lish".

utils/pub/command_lish.dart

Index: utils/pub/command_lish.dart
diff --git a/utils/pub/command_lish.dart b/utils/pub/command_lish.dart
index c2def2f15208b7cf61ba34169253dd5c8c43fb15..93df4ffa429562f6c1c33ae108c4c308eae5849c 100644
--- a/utils/pub/command_lish.dart
+++ b/utils/pub/command_lish.dart
@@ -14,6 +14,7 @@ import 'pub.dart';
 import 'io.dart';
 import 'git.dart' as git;
 import 'oauth2.dart' as oauth2;
+import 'validator.dart';
 
 // TODO(nweiz): Make "publish" the primary name for this command. See issue
 // 6949.
@@ -51,7 +52,8 @@ class LishCommand extends PubCommand {
         client.get(server.resolve("/packages/versions/new.json")),
         _filesToPublish.transform((files) {
           return createTarGz(files, baseDir: entrypoint.root.dir);
-        }).chain(consumeInputStream)
+        }).chain(consumeInputStream),
+        Validator.runAll(cache, entrypoint)
       ]).chain((results) {
         var response = results[0];
         var packageBytes = results[1];