Suppress a few analysis warnings in the analyzer codebase.

pkg/analyzer_plugin/lib/plugin/plugin.dart

 // Copyright (c) 2017, 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.
 
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/dart/analysis/byte_store.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart'
     show AnalysisDriverScheduler, PerformanceLog;
 import 'package:analyzer/src/dart/analysis/file_byte_store.dart';
 import 'package:analyzer/src/dart/analysis/file_state.dart';
@@ skipping 45 matching lines @@
    * The performance log used by any analysis drivers that are created.
    */
   final PerformanceLog performanceLog =
       new PerformanceLog(new NullStringSink());
 
   /**
    * The byte store used by any analysis drivers that are created, or `null` if
    * the cache location isn't known because the 'plugin.version' request has not
    * yet been received.
    */
-  ByteStore _byteStore;
+  ByteStore _byteStore; // ignore: unused_field

[scheglov, 2017/02/10 21:06:53]

I think Brian will use it eventually, and again, I think it's OK to keep it
visible so that we don't hide and forget about it.

[devoncarew, 2017/02/10 21:12:35]

Removed the ignore.

 
   /**
    * The file content overlay used by any analysis drivers that are created.
    */
   final FileContentOverlay fileContentOverlay = new FileContentOverlay();
 
   /**
    * Initialize a newly created analysis server plugin. If a resource [provider]
    * is given, then it will be used to access the file system. Otherwise a
    * resource provider that accesses the physical file system will be used.
@@ skipping 319 matching lines @@
       response = new Response(id,
           error: new RequestError(
               RequestErrorCode.PLUGIN_ERROR, exception.toString(),
               stackTrace: stackTrace.toString()));
     }
     if (response != null) {
       _channel.sendResponse(response);
     }
   }
 }