Add optimized _OneByteString.toLowerCase.

sdk/lib/io/http_impl.dart

 // Copyright (c) 2013, 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.io;
 
 const int _OUTGOING_BUFFER_SIZE = 8 * 1024;
 
 class _HttpIncoming extends Stream<List<int>> {
   final int _transferLength;
@@ skipping 346 matching lines @@
       // as they must have already been added to the request causing
       // this authenticate response.
       if (cr.scheme == _AuthenticationScheme.BASIC && !cr.used) {
         // Credentials where found, prepare for retrying the request.
         return retry();
       }
 
       // Digest authentication only supports the MD5 algorithm.
       if (cr.scheme == _AuthenticationScheme.DIGEST &&
           (header.parameters["algorithm"] == null ||
-           header.parameters["algorithm"].toLowerCase() == "md5")) {
+           _ASCII.toLowerCase(header.parameters["algorithm"]) == "md5")) {
         if (cr.nonce == null || cr.nonce == header.parameters["nonce"]) {
           // If the nonce is not set then this is the first authenticate
           // response for these credentials. Set up authentication state.
           if (cr.nonce == null) {
             cr..nonce = header.parameters["nonce"]
               ..algorithm = "MD5"
               ..qop = header.parameters["qop"]
               ..nonceCount = 0;
           }
           // Credentials where found, prepare for retrying the request.
           return retry();
         } else if (header.parameters["stale"] != null &&
-                   header.parameters["stale"].toLowerCase() == "true") {
+                   _ASCII.toLowerCase(header.parameters["stale"]) == "true") {
           // If stale is true retry with new nonce.
           cr.nonce = header.parameters["nonce"];
           // Credentials where found, prepare for retrying the request.
           return retry();
         }
       }
     }
 
     // Ask for more credentials if none found or the one found has
     // already been used. If it has already been used it must now be
@@ skipping 528 matching lines @@
     bool gzip = false;
     if (isServerSide) {
       var response = outbound;
       if (outbound.headers.chunkedTransferEncoding) {
         List acceptEncodings =
             response._httpRequest.headers[HttpHeaders.ACCEPT_ENCODING];
         List contentEncoding = outbound.headers[HttpHeaders.CONTENT_ENCODING];
         if (acceptEncodings != null &&
             acceptEncodings
                 .expand((list) => list.split(","))
-                .any((encoding) => encoding.trim().toLowerCase() == "gzip") &&
+                .any((encoding) =>
+                    _ASCII.toLowerCase(encoding.trim()) == "gzip") &&
             contentEncoding == null) {
           outbound.headers.set(HttpHeaders.CONTENT_ENCODING, "gzip");
           gzip = true;
         }
       }
       if (drainRequest && !response._httpRequest._incoming.hasSubscriber) {
         drainFuture = response._httpRequest.drain().catchError((_) {});
       }
     } else {
       drainRequest = false;
@@ skipping 1402 matching lines @@
 class _AuthenticationScheme {
   final int _scheme;
 
   static const UNKNOWN = const _AuthenticationScheme(-1);
   static const BASIC = const _AuthenticationScheme(0);
   static const DIGEST = const _AuthenticationScheme(1);
 
   const _AuthenticationScheme(this._scheme);
 
   factory _AuthenticationScheme.fromString(String scheme) {
-    if (scheme.toLowerCase() == "basic") return BASIC;
-    if (scheme.toLowerCase() == "digest") return DIGEST;
+    scheme = _ASCII.toLowerCase(scheme);
+    if (scheme == "basic") return BASIC;
+    if (scheme == "digest") return DIGEST;
     return UNKNOWN;
   }
 
   String toString() {
     if (this == BASIC) return "Basic";
     if (this == DIGEST) return "Digest";
     return "Unknown";
   }
 }
 
@@ skipping 213 matching lines @@
   const _RedirectInfo(this.statusCode, this.method, this.location);
 }
 
 String _getHttpVersion() {
   var version = Platform.version;
   // Only include major and minor version numbers.
   int index = version.indexOf('.', version.indexOf('.') + 1);
   version = version.substring(0, index);
   return 'Dart/$version (dart:io)';
 }