Fix some bad documentation links.

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;
 
 // Frequently used character codes.
 const int _SPACE = 0x20;
 const int _PERCENT = 0x25;
 const int _AMPERSAND = 0x26;
@@ skipping 265 matching lines @@
    * then encodes the bytes into the resulting data URI.
    *
    * Defaults to encoding using percent-encoding (any non-ASCII or non-URI-valid
    * bytes is replaced by a percent encoding). If [base64] is true, the bytes
    * are instead encoded using [BASE64].
    *
    * If [encoding] is not provided and [parameters] has a `charset` entry,
    * that name is looked up using [Encoding.getByName],
    * and if the lookup returns an encoding, that encoding is used to convert
    * [content] to bytes.
-   * If providing both an [encoding] and a charset [parameter], they should
+   * If providing both an [encoding] and a charset in [parameters], they should
    * agree, otherwise decoding won't be able to use the charset parameter
    * to determine the encoding.
    *
    * If [mimeType] and/or [parameters] are supplied, they are added to the
    * created URI. If any of these contain characters that are not allowed
    * in the data URI, the character is percent-escaped. If the character is
    * non-ASCII, it is first UTF-8 encoded and then the bytes are percent
    * encoded. An omitted [mimeType] in a data URI means `text/plain`, just
    * as an omitted `charset` parameter defaults to meaning `US-ASCII`.
    *
@@ skipping 4333 matching lines @@
   int delta = (text.codeUnitAt(start + 4) ^ _COLON) * 3;
   delta |= text.codeUnitAt(start) ^ 0x64 /*d*/;
   delta |= text.codeUnitAt(start + 1) ^ 0x61 /*a*/;
   delta |= text.codeUnitAt(start + 2) ^ 0x74 /*t*/;
   delta |= text.codeUnitAt(start + 3) ^ 0x61 /*a*/;
   return delta;
 }
 
 /// Helper function returning the length of a string, or `0` for `null`.
 int _stringOrNullLength(String s) => (s == null) ? 0 : s.length;