Revert "Reapply "[ Service ] Start DDS and serve DevTools when the VM service is started via dart:developer""

This reverts commit 44d4451.

Reason for revert: b/350443042

Original change's description:
> Reapply "[ Service ] Start DDS and serve DevTools when the VM service is started via dart:developer"
>
> In the previous version of this change, if the user had 'dart' on their
> PATH and invoked 'dart compile js' (which spawns the VM service after
> compilation completes), the VM service would attempt to spawn DDS using
> './dart' as the executable path instead of 'dart'. This would result in
> DDS failing to start, causing the VM to print an error and hang.
>
> This updated change checks to see if the parent directory of
> `Platform.executable` is '.' and then verifies if './dart' exists or
> not. If it doesn't, 'dart' is likely on the user's PATH and should be
> used directly as the executable path.
>
> See #56087 for details.
>
> This reverts commit 4b88698.
>
> TEST=pkg/dds/test/control_web_server_starts_dds_with_dart_on_path_test.dart
>
> Change-Id: Id0f1dadd01d9202cbf7717f31393b43171cf3968
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/373561
> Auto-Submit: Ben Konyi <[email protected]>
> Reviewed-by: Derek Xu <[email protected]>
> Commit-Queue: Ben Konyi <[email protected]>

Change-Id: I424c4b91b0b108ae4c9dffa0059ed90c918897e3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/373744
Reviewed-by: Siva Annamalai <[email protected]>
Bot-Commit: Rubber Stamper <[email protected]>
Reviewed-by: Srujan Gaddam <[email protected]>
Commit-Queue: Siva Annamalai <[email protected]>
Auto-Submit: Ivan Inozemtsev <[email protected]>

Author: iinozemtsev

pkg/dds/test/control_web_server_starts_dds_test.dart

@@ -15,7 +15,7 @@ Uri? wsServerUri;
 
 Future<Null> testeeBefore() async {
   print('testee before');
-  // First grab the URL where the VM service is listening and the
+  // First grab the URL where the observatory is listening on and the
   // service protocol version numbers. We expect the URL to be null as
   // the server has not been started yet.
   ServiceProtocolInfo info = await Service.getInfo();

pkg/dds/test/control_web_server_starts_dds_with_dart_on_path_test.dart

@@ -96,21 +96,11 @@ class _DebuggingSession {
     bool disableServiceAuthCodes,
     bool enableDevTools,
   ) async {
-    final dartDir = File(Platform.executable).parent.path;
-    final dart = 'dart${Platform.isWindows ? '.exe' : ''}';
-    var executable = [
+    final dartDir = File(Platform.resolvedExecutable).parent.path;
+    final executable = [
       dartDir,
-      dart,
+      'dart${Platform.isWindows ? '.exe' : ''}',
     ].join(Platform.pathSeparator);
-
-    // If the directory of dart is '.' it's likely that dart is on the user's
-    // PATH. If so, './dart' might not exist and we should be using 'dart'
-    // instead.
-    if (dartDir == '.' &&
-        (await FileSystemEntity.type(executable)) ==
-            FileSystemEntityType.notFound) {
-      executable = dart;
-    }
     _process = await Process.start(
       executable,
       [
@@ -143,15 +133,15 @@ class _DebuggingSession {
           // is changed to ensure consistency.
           const devToolsMessagePrefix =
               'The Dart DevTools debugger and profiler is available at:';
-          serverPrint('$devToolsMessagePrefix $devToolsUri');
+          print('$devToolsMessagePrefix $devToolsUri');
         }
         if (result
             case {
               'dtd': {
                 'uri': String dtdUri,
               }
             } when _printDtd) {
-          serverPrint('The Dart Tooling Daemon (DTD) is available at: $dtdUri');
+          print('The Dart Tooling Daemon (DTD) is available at: $dtdUri');
         }
       } else {
         printError(result['error'] ?? result);
@@ -318,37 +308,18 @@ Future<List<Map<String, dynamic>>> listFilesCallback(Uri dirPath) async {
 
 Uri? serverInformationCallback() => _lazyServerBoot().serverAddress;
 
-Future<void> _toggleWebServer(Server server) async {
-  // Toggle HTTP server.
-  if (server.running) {
-    await server.shutdown(true).then((_) async {
-      ddsInstance?.shutdown();
-      ddsInstance = null;
-      await VMService().clearState();
-      serverFuture = null;
-    });
-  } else {
-    await server.startup().then((_) async {
-      if (_waitForDdsToAdvertiseService) {
-        ddsInstance = _DebuggingSession();
-        await ddsInstance!.start(
-          _ddsIP,
-          _ddsPort.toString(),
-          _authCodesDisabled,
-          _serveDevtools,
-        );
-      }
-    });
-  }
-}
-
 Future<Uri?> webServerControlCallback(bool enable, bool? silenceOutput) async {
   if (silenceOutput != null) {
     silentObservatory = silenceOutput;
   }
   final _server = _lazyServerBoot();
   if (_server.running != enable) {
-    await _toggleWebServer(_server);
+    if (enable) {
+      await _server.startup();
+      // TODO: if dds is enabled a dds instance needs to be started.
+    } else {
+      await _server.shutdown(true);
+    }
   }
   return _server.serverAddress;
 }
@@ -358,13 +329,32 @@ void webServerAcceptNewWebSocketConnections(bool enable) {
   _server.acceptNewWebSocketConnections = enable;
 }
 
-Future<void> _onSignal(ProcessSignal signal) async {
+_onSignal(ProcessSignal signal) async {
   if (serverFuture != null) {
     // Still waiting.
     return;
   }
-  final server = _lazyServerBoot();
-  await _toggleWebServer(server);
+  final _server = _lazyServerBoot();
+  // Toggle HTTP server.
+  if (_server.running) {
+    _server.shutdown(true).then((_) async {
+      ddsInstance?.shutdown();
+      await VMService().clearState();
+      serverFuture = null;
+    });
+  } else {
+    _server.startup().then((_) {
+      if (_waitForDdsToAdvertiseService) {
+        ddsInstance = _DebuggingSession()
+          ..start(
+            _ddsIP,
+            _ddsPort.toString(),
+            _authCodesDisabled,
+            _serveDevtools,
+          );
+      }
+    });
+  }
 }
 
 Timer? _registerSignalHandlerTimer;
@@ -410,10 +400,18 @@ main() {
   // can be delivered and waiting loaders can be cancelled.
   VMService();
   if (_autoStart) {
-    assert(server == null);
     final _server = _lazyServerBoot();
-    assert(!_server.running);
-    _toggleWebServer(_server);
+    _server.startup().then((_) {
+      if (_waitForDdsToAdvertiseService) {
+        ddsInstance = _DebuggingSession()
+          ..start(
+            _ddsIP,
+            _ddsPort.toString(),
+            _authCodesDisabled,
+            _serveDevtools,
+          );
+      }
+    });
     // It's just here to push an event on the event loop so that we invoke the
     // scheduled microtasks.
     Timer.run(() {});