Mark Dartium and content shell as isDartVM.

lib/src/backend/platform_selector/evaluator.dart

Index: lib/src/backend/platform_selector/evaluator.dart
diff --git a/lib/src/backend/platform_selector/evaluator.dart b/lib/src/backend/platform_selector/evaluator.dart
index 3f61fcc34758d7fe379411d80e5cee3195ac7ebb..7078e18fc8b433025c5b35bf167771982bac1653 100644
--- a/lib/src/backend/platform_selector/evaluator.dart
+++ b/lib/src/backend/platform_selector/evaluator.dart
@@ -26,7 +26,7 @@ class Evaluator implements Visitor<bool> {
     if (node.name == _os.name) return true;
 
     switch (node.name) {
-      case "dart-vm": return _platform.isDartVm;
+      case "dart-vm": return _platform.isDartVM;
       case "browser": return _platform.isBrowser;
       case "js": return _platform.isJS;
       case "blink": return _platform.isBlink;