Fix a bug where an action bar could be created when it should not be.

Change-Id: I9ca1038accdb6d0a539750ed8ab068a41612f6ae
diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index edfd6ef..fc4d12c 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -1760,6 +1760,11 @@
      */
     private void initActionBar() {
         Window window = getWindow();
+
+        // Initializing the window decor can change window feature flags.
+        // Make sure that we have the correct set before performing the test below.
+        window.getDecorView();
+
         if (isChild() || !window.hasFeature(Window.FEATURE_ACTION_BAR) || mActionBar != null) {
             return;
         }