Remove unnecessary ignore comment

Change-Id: I40bdf75ccfc0d22c93dfbb7bbea5c860198b065b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/217022
Auto-Submit: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
Reviewed-by: Ben Konyi <bkonyi@google.com>

pkg/dartdev/lib/src/analysis_server.dart

@@ -95,7 +95,6 @@ class AnalysisServer {
 
     _process = await startDartProcess(sdk, command);
     // This callback hookup can't throw.
-    // ignore: unawaited_futures
     _process.exitCode.whenComplete(() => _process = null);
 
     final Stream<String> errorStream = _process.stderr
@@ -110,7 +109,6 @@ class AnalysisServer {
 
     _streamController('server.error').stream.listen(_handleServerError);
 
-    // ignore: unawaited_futures
     _sendCommand('server.setSubscriptions', params: <String, dynamic>{
       'subscriptions': <String>['STATUS'],
     });
@@ -136,7 +134,6 @@ class AnalysisServer {
       }
     });
 
-    // ignore: unawaited_futures
     _sendCommand('analysis.setAnalysisRoots', params: <String, dynamic>{
       'included': analysisRootPaths,
       'excluded': <String>[]

pkg/dartdev/lib/src/commands/analyze.dart

@@ -128,7 +128,6 @@ class AnalyzeCommand extends DartdevCommand {
 
     bool analysisFinished = false;
 
-    // ignore: unawaited_futures
     server.onExit.then((int exitCode) {
       if (!analysisFinished) {
         io.exitCode = exitCode;

pkg/dartdev/lib/src/commands/fix.dart

@@ -100,7 +100,6 @@ To use the tool, run either ['dart fix --dry-run'] for a preview of the proposed
     await server.start();
 
     EditBulkFixesResult fixes;
-    //ignore: unawaited_futures
     server.onExit.then((int exitCode) {
       if (fixes == null && exitCode != 0) {
         progress?.cancel();