[MV3 Debug Extension] Fix isDevMode getter (dart-lang#1962)

Author: elliette

dwds/debug_extension_mv3/web/background.dart

@@ -142,9 +142,8 @@ void _setDebuggableIcon() {
 }
 
 void _setDefaultIcon() {
-  final iconPath = isDevMode()
-      ? 'static_assets/dart_dev.png'
-      : 'static_assets/dart_grey.png';
+  final iconPath =
+      isDevMode ? 'static_assets/dart_dev.png' : 'static_assets/dart_grey.png';
   setExtensionIcon(IconInfo(path: iconPath));
 }
 

dwds/debug_extension_mv3/web/devtools.dart

@@ -44,7 +44,7 @@ void _maybeCreatePanels() async {
   if (!isInternalBuild) return;
   // Create a Debugger panel for all internal apps:
   chrome.devtools.panels.create(
-    isDevMode() ? '[DEV] Dart Debugger' : 'Dart Debugger',
+    isDevMode ? '[DEV] Dart Debugger' : 'Dart Debugger',
     '',
     'static_assets/debugger_panel.html',
     allowInterop((ExtensionPanel panel) => _onPanelAdded(panel, debugInfo)),
@@ -53,7 +53,7 @@ void _maybeCreatePanels() async {
   final isFlutterApp = debugInfo.isFlutterApp ?? false;
   if (isFlutterApp) {
     chrome.devtools.panels.create(
-      isDevMode() ? '[DEV] Flutter Inspector' : 'Flutter Inspector',
+      isDevMode ? '[DEV] Flutter Inspector' : 'Flutter Inspector',
       '',
       'static_assets/inspector_panel.html',
       allowInterop((ExtensionPanel panel) => _onPanelAdded(panel, debugInfo)),

dwds/debug_extension_mv3/web/logger.dart

@@ -45,7 +45,7 @@ void _log(
   _LogLevel? level,
   String? prefix,
 }) {
-  if (!verbose && !isDevMode()) return;
+  if (!verbose && !isDevMode) return;
   final logMsg = prefix != null ? '[$prefix] $msg' : msg;
   final logLevel = level ?? _LogLevel.info;
   switch (logLevel) {

dwds/debug_extension_mv3/web/utils.dart

@@ -86,13 +86,15 @@ void setExtensionIcon(IconInfo info) {
 
 bool? _isDevMode;
 
-bool isDevMode() {
+bool get isDevMode {
   if (_isDevMode != null) {
     return _isDevMode!;
   }
   final extensionManifest = chrome.runtime.getManifest();
   final extensionName = getProperty(extensionManifest, 'name') ?? '';
-  return extensionName.contains('DEV');
+  final isDevMode = extensionName.contains('DEV');
+  _isDevMode = isDevMode;
+  return isDevMode;
 }
 
 String addQueryParameters(