Reland "Added --dart-flags option to flutter run (#33924)" (#34181)

Reland "Added --dart-flags option to flutter run (#33924)"

This reverts commit 587687eedf81aa83521cca96b8fb65a4adc8dd90.

packages/flutter_tools/lib/src/device.dart

diff --git a/packages/flutter_tools/lib/src/device.dart b/packages/flutter_tools/lib/src/device.dart
index 394befb..3947ce3 100644
--- a/packages/flutter_tools/lib/src/device.dart
+++ b/packages/flutter_tools/lib/src/device.dart
@@ -377,6 +377,7 @@
     this.buildInfo, {
     this.startPaused = false,
     this.disableServiceAuthCodes = false,
+    this.dartFlags = '',
     this.enableSoftwareRendering = false,
     this.skiaDeterministicRendering = false,
     this.traceSkia = false,
@@ -391,6 +392,7 @@
     : debuggingEnabled = false,
       useTestFonts = false,
       startPaused = false,
+      dartFlags = '',
       disableServiceAuthCodes = false,
       enableSoftwareRendering = false,
       skiaDeterministicRendering = false,
@@ -404,6 +406,7 @@
 
   final BuildInfo buildInfo;
   final bool startPaused;
+  final String dartFlags;
   final bool disableServiceAuthCodes;
   final bool enableSoftwareRendering;
   final bool skiaDeterministicRendering;