Change new Uri(query:"") to not add a query part.

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 470 matching lines @@
    *
    * The query component is set through either [query] or
    * [queryParameters]. When [query] is used the provided string should
    * be a valid URI query, but invalid characters other than general delimiters,
    * will be escaped if necessary.
    * When [queryParameters] is used the query is built from the
    * provided map. Each key and value in the map is percent-encoded
    * and joined using equal and ampersand characters. The
    * percent-encoding of the keys and values encodes all characters
    * except for the unreserved characters.
+   * If `query` is the empty string, it is equivalent to omitting it.
+   * To have an actual empty query part,
+   * use an empty list for `queryParameters`.
    * If both `query` and `queryParameters` are omitted or `null`, the
    * URI will have no query part.
    *
    * The fragment component is set through [fragment].
    * It should be a valid URI fragment, but invalid characters other than
    * general delimiters, will be escaped if necessary.
    * If `fragment` is omitted or `null`, the URI will have no fragment part.
    */
   factory Uri({String scheme : "",
                String userInfo : "",
                String host,
                int port,
                String path,
                Iterable<String> pathSegments,
                String query,
                Map<String, String> queryParameters,
                fragment}) {
     scheme = _makeScheme(scheme, _stringOrNullLength(scheme));
     userInfo = _makeUserInfo(userInfo, 0, _stringOrNullLength(userInfo));
     host = _makeHost(host, 0, _stringOrNullLength(host), false);
+    // Special case this constructor for backwards compatibility.

[Anders Johnsen, 2014/06/26 11:04:32]

TODO for deprecating this behavior in 2.0?

[Lasse Reichstein Nielsen, 2014/06/26 11:14:04]

I'll put it on my list, but we are not putting 2.0 comments into the code yet.

+    if (query == "") query = null;
     query = _makeQuery(query, 0, _stringOrNullLength(query), queryParameters);
     fragment = _makeFragment(fragment, 0, _stringOrNullLength(fragment));
     port = _makePort(port, scheme);
     bool isFile = (scheme == "file");
     if (host == null &&
         (userInfo.isNotEmpty || port != null || isFile)) {
       host = "";
     }
     bool ensureLeadingSlash = (host != null || isFile);
     path = _makePath(path, 0, _stringOrNullLength(path), pathSegments,
@@ skipping 1753 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
 }