Update documentation of Uri.parse.

sdk/lib/core/uri.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.core;
 
 /**
  * A parsed URI, such as a URL.
  *
  * **See also:**
@@ skipping 139 matching lines @@
    */
   Map<String, String> _queryParameters;
 
   /**
    * Creates a new `Uri` object by parsing a URI string.
    *
    * If [start] and [end] are provided, only the substring from `start`
    * to `end` is parsed as a URI.
    *
    * If the string is not valid as a URI or URI reference,
-   * invalid characters will be percent escaped where possible.
-   * The resulting `Uri` will represent a valid URI or URI reference.
+   * a [FormatException] is thrown.
    */
   static Uri parse(String uri, [int start = 0, int end]) {
-    // This parsing will not validate percent-encoding, IPv6, etc. When done
-    // it will call `new Uri(...)` which will perform these validations.
-    // This is purely splitting up the URI string into components.
+    // This parsing will not validate percent-encoding, IPv6, etc.
+    // When done splitting into parts, it will call, e.g., [_makeFragment]
+    // to do the final parsing.
     //
     // Important parts of the RFC 3986 used here:
     // URI           = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
     //
     // hier-part     = "//" authority path-abempty
     //               / path-absolute
     //               / path-rootless
     //               / path-empty
     //
     // URI-reference = URI / relative-ref
@@ skipping 2294 matching lines @@
       0xafff,   // 0x30 - 0x3f  1111111111110101
                 //              @ABCDEFGHIJKLMNO
       0xffff,   // 0x40 - 0x4f  1111111111111111
                 //              PQRSTUVWXYZ    _
       0x87ff,   // 0x50 - 0x5f  1111111111100001
                 //               abcdefghijklmno
       0xfffe,   // 0x60 - 0x6f  0111111111111111
                 //              pqrstuvwxyz   ~
       0x47ff];  // 0x70 - 0x7f  1111111111100010
 }