IDEA-156245 @NotNull doesn't seem to work for enums

java/java-tests/testData/inspection/dataFlow/fixture/CheckEnumConstantConstructor.java

@@ -0,0 +1,19 @@
+import org.jetbrains.annotations.*;
+
+enum NotNullEnum {
+  ONE("One"),
+  TWO(<warning descr="Passing 'null' argument to parameter annotated as @NotNull">null</warning>),
+  THREE(<warning descr="Passing 'null' argument to parameter annotated as @NotNull">null</warning>) {};
+
+  private final @NotNull String param;
+  NotNullEnum(@NotNull String param) {
+    this.param = param;
+  }
+  @NotNull
+  public String getParam() {
+    return param;
+  }
+  public static void main(String[] args) {
+    NotNullEnum one = ONE;
+  }
+}