Spelling fixes e to i.

sdk/lib/io/stdio.dart

Index: sdk/lib/io/stdio.dart
diff --git a/sdk/lib/io/stdio.dart b/sdk/lib/io/stdio.dart
index 7473706eb0d1475bdb45d64f1cf2e59f45150bba..45e7fdc41f9564fbb8feb2eb13e87994849adf5b 100644
--- a/sdk/lib/io/stdio.dart
+++ b/sdk/lib/io/stdio.dart
@@ -79,7 +79,7 @@ class Stdin extends _StdStream implements Stream<List<int>> {
         line.add(byte);
       }
     } else {
-      // Case having to handel CR LF as a single unretained line terminator.
+      // Case having to handle CR LF as a single unretained line terminator.
       outer:
       while (true) {
         int byte = readByteSync();