Use lazy static fields when overriding static getters or setters.

lib/src/compiler/js_field_storage.dart

Index: lib/src/compiler/js_field_storage.dart
diff --git a/lib/src/compiler/js_field_storage.dart b/lib/src/compiler/js_field_storage.dart
index 7a4b0174922966982c31fcb40a9c3049e209a349..29b5a77a67e7c72438a33d665d6091da1679a69a 100644
--- a/lib/src/compiler/js_field_storage.dart
+++ b/lib/src/compiler/js_field_storage.dart
@@ -28,6 +28,10 @@ PropertyOverrideResult checkForPropertyOverride(FieldElement field,
     var superprop = getProperty(superclass, field.library, field.name);
     if (superprop == null) continue;
 
+    // Static fields can override superclass static fields. However, we need to
+    // handle the case where they override a getter or setter.
+    if (field.isStatic && !superprop.isSynthetic) continue;
+
     var getter = superprop.getter;
     bool hasGetter = getter != null && !getter.isAbstract;
     if (hasGetter) foundGetter = true;