Add global key configuration file

Add global key configuration file. A global key is one that is handled by
PhoneWindowManager before dispatching and sent to a given component via
broadcast instead of going to the foreground app.
Bug: 8510681

Change-Id: Ic6a8e559680d005613ed22874b27eb78bbfc4499
diff --git a/core/java/android/content/Intent.java b/core/java/android/content/Intent.java
index 0efd6b0..c9b9a1a 100644
--- a/core/java/android/content/Intent.java
+++ b/core/java/android/content/Intent.java
@@ -2578,6 +2578,14 @@
     public static final String ACTION_SHOW_BRIGHTNESS_DIALOG =
             "android.intent.action.SHOW_BRIGHTNESS_DIALOG";
 
+    /**
+     * Broadcast Action:  A global button was pressed.  Includes a single
+     * extra field, {@link #EXTRA_KEY_EVENT}, containing the key event that
+     * caused the broadcast.
+     * @hide
+     */
+    public static final String ACTION_GLOBAL_BUTTON = "android.intent.action.GLOBAL_BUTTON";
+
     // ---------------------------------------------------------------------
     // ---------------------------------------------------------------------
     // Standard intent categories (see addCategory()).