Change getRange to sublist. Make getRange deprecated.

sdk/lib/io/mime_multipart_parser.dart

Index: sdk/lib/io/mime_multipart_parser.dart
diff --git a/sdk/lib/io/mime_multipart_parser.dart b/sdk/lib/io/mime_multipart_parser.dart
index 0721e46c151a4ad0dae0d787aa27373ac20b82b4..cd12c2023394413046e0dd2449b8d8b8d416ba0a 100644
--- a/sdk/lib/io/mime_multipart_parser.dart
+++ b/sdk/lib/io/mime_multipart_parser.dart
@@ -79,17 +79,17 @@ class _MimeMultipartParser {
         var contentLength = boundaryPrefix + index - _boundaryIndex;
         if (contentLength <= boundaryPrefix) {
           partDataReceived(
-              _boundary.getRange(0, contentLength));
+              _boundary.sublist(0, contentLength));
         } else {
           partDataReceived(
-              _boundary.getRange(0, boundaryPrefix));
+              _boundary.sublist(0, boundaryPrefix));
           partDataReceived(
-              buffer.getRange(0, contentLength - boundaryPrefix));
+              buffer.sublist(0, contentLength - boundaryPrefix));
         }
       } else {
-        var contentLength = index - contentStartIndex - _boundaryIndex;
+        var contentEndIndex = index - _boundaryIndex;
         partDataReceived(
-            buffer.getRange(contentStartIndex, contentLength));
+            buffer.sublist(contentStartIndex, contentEndIndex));
       }
     }