Fix all the analysis hints in pub.

sdk/lib/_internal/pub/lib/src/io.dart

Index: sdk/lib/_internal/pub/lib/src/io.dart
diff --git a/sdk/lib/_internal/pub/lib/src/io.dart b/sdk/lib/_internal/pub/lib/src/io.dart
index d3c779b33f5814017475ed00b5980e8186b61566..687157a81dfdb16dbda0c2e1cd7336cae4d4c02f 100644
--- a/sdk/lib/_internal/pub/lib/src/io.dart
+++ b/sdk/lib/_internal/pub/lib/src/io.dart
@@ -418,7 +418,7 @@ void renameDir(String from, String to) {
     log.io("Renaming directory $from to $to.");
     try {
       new Directory(from).renameSync(to);
-    } on IOException catch (error) {
+    } on IOException {
       // Ensure that [to] isn't left in an inconsistent state. See issue 12436.
       if (entryExists(to)) deleteEntry(to);
       rethrow;
@@ -1017,9 +1017,3 @@ class PubProcessResult {
 
   bool get success => exitCode == exit_codes.SUCCESS;
 }
-
-/// Gets a [Uri] for [uri], which can either already be one, or be a [String].
-Uri _getUri(uri) {
-  if (uri is Uri) return uri;
-  return Uri.parse(uri);
-}