Send SHUTDOWN bc to registered receivers only

Test: adb shell svc power reboot
Bug: 65174075
Change-Id: I652c7564b989736c9deabd0989abdb1e44f3b78a
diff --git a/core/java/android/content/Intent.java b/core/java/android/content/Intent.java
index b3c8737..40712f1 100644
--- a/core/java/android/content/Intent.java
+++ b/core/java/android/content/Intent.java
@@ -2508,6 +2508,9 @@
      * off, not sleeping).  Once the broadcast is complete, the final shutdown
      * will proceed and all unsaved data lost.  Apps will not normally need
      * to handle this, since the foreground activity will be paused as well.
+     * <p>As of {@link Build.VERSION_CODES#P} this broadcast is only sent to receivers registered
+     * through {@link Context#registerReceiver(BroadcastReceiver, IntentFilter)
+     * Context.registerReceiver}.
      *
      * <p class="note">This is a protected intent that can only be sent
      * by the system.