Fix 'Unused local variable' hints in analyzer and analysis_server.

pkg/analyzer/lib/src/services/writer.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.
 
 library source_writer;
 
 import 'dart:math' as math;
 
 class Line {
 
@@ skipping 139 matching lines @@
                     length = 0;
                     continue;
                   }
                 }
                 length += token.length;
               }
               if (start < tokens.length) {
                 newChunks.add(chunk.subChunk(newIndent, start));
               }
             } else {
-              List<LineToken> part = [];
               int start = 0;
               for (int i = 0; i < tokens.length; i++) {
                 LineToken token = tokens[i];
                 if (token is SpaceToken && token.breakWeight == weight) {
                   newChunks.add(chunk.subChunk(newIndent, start, i));
                   newIndent = chunk.indent + 2;
                   start = i + 1;
                 }
               }
               if (start < tokens.length) {
@@ skipping 338 matching lines @@
 
 String getTabs(int n) => n < TABS.length ? TABS[n] : repeat('\t', n);
 
 String repeat(String ch, int times) {
   var sb = new StringBuffer();
   for (var i = 0; i < times; ++i) {
     sb.write(ch);
   }
   return sb.toString();
 }