fix wrong CRLF grapheme

lib/elixir/test/elixir/string_test.exs

@@ -208,6 +208,7 @@ defmodule StringTest do
     assert String.reverse("Hello ∂og") == "go∂ olleH"
     assert String.reverse("Ā̀stute") == "etutsĀ̀"
     assert String.reverse(String.reverse("Hello World")) == "Hello World"
+    assert String.reverse(String.reverse("Hello \r\n World")) == "Hello \r\n World"
   end
 
   test :replace do
@@ -257,7 +258,7 @@ defmodule StringTest do
     # Extended
     assert String.graphemes("Ā̀stute") == ["Ā̀", "s", "t", "u", "t", "e"]
     # CLRF
-    assert String.graphemes("\n\r\f") == ["\n\r", "\f"]
+    assert String.graphemes("\r\n\f") == ["\r\n", "\f"]
     # Regional indicator
     assert String.graphemes("\x{1F1E6}\x{1F1E7}\x{1F1E8}") == ["\x{1F1E6}\x{1F1E7}\x{1F1E8}"]
     # Hangul

lib/elixir/unicode/unicode.ex

@@ -208,8 +208,8 @@ defmodule String.Graphemes do
   end
 
   # Don't break CRLF
-  def next_grapheme(<< ?\n, ?\r, rest :: binary >>) do
-    {"\n\r", rest}
+  def next_grapheme(<< ?\r, ?\n, rest :: binary >>) do
+    {"\r\n", rest}
   end
 
   # Break on control