Poke interactive hint from userActivity and add @SystemApi.

Previously we only poked the interactive hint for input events that
were dispatched through the regular input system.  However, when
using a car dock in projection mode input events are directly
delivered to apps by other system components, bypassing user activity.
So now we poke the interactive hint on all user activity.

Added an @SystemApi version of userActivity.

Added a new signature|system permission called USER_ACTIVITY
to allow system apps to poke userActivity.  For now it seems
prudent to keep DEVICE_POWER signature only.

Bug: 17043684
Change-Id: Ia84bd03083065b8938a9853c08901fbf71b2e56b
diff --git a/core/java/android/os/PowerManager.java b/core/java/android/os/PowerManager.java
index 67ec563..4b206e3 100644
--- a/core/java/android/os/PowerManager.java
+++ b/core/java/android/os/PowerManager.java
@@ -17,6 +17,7 @@
 package android.os;
 
 import android.annotation.SdkConstant;
+import android.annotation.SystemApi;
 import android.content.Context;
 import android.util.Log;
 
@@ -274,28 +275,44 @@
      * User activity event type: Unspecified event type.
      * @hide
      */
+    @SystemApi
     public static final int USER_ACTIVITY_EVENT_OTHER = 0;
 
     /**
      * User activity event type: Button or key pressed or released.
      * @hide
      */
+    @SystemApi
     public static final int USER_ACTIVITY_EVENT_BUTTON = 1;
 
     /**
      * User activity event type: Touch down, move or up.
      * @hide
      */
+    @SystemApi
     public static final int USER_ACTIVITY_EVENT_TOUCH = 2;
 
     /**
-     * User activity flag: Do not restart the user activity timeout or brighten
-     * the display in response to user activity if it is already dimmed.
+     * User activity flag: If already dimmed, extend the dim timeout
+     * but do not brighten.  This flag is useful for keeping the screen on
+     * a little longer without causing a visible change such as when
+     * the power key is pressed.
      * @hide
      */
+    @SystemApi
     public static final int USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS = 1 << 0;
 
     /**
+     * User activity flag: Note the user activity as usual but do not
+     * reset the user activity timeout.  This flag is useful for applying
+     * user activity power hints when interacting with the device indirectly
+     * on a secondary screen while allowing the primary screen to go to sleep.
+     * @hide
+     */
+    @SystemApi
+    public static final int USER_ACTIVITY_FLAG_INDIRECT = 1 << 1;
+
+    /**
      * Go to sleep reason code: Going to sleep due by application request.
      * @hide
      */
@@ -506,9 +523,38 @@
      * @see #goToSleep
      */
     public void userActivity(long when, boolean noChangeLights) {
+        userActivity(when, USER_ACTIVITY_EVENT_OTHER,
+                noChangeLights ? USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS : 0);
+    }
+
+    /**
+     * Notifies the power manager that user activity happened.
+     * <p>
+     * Resets the auto-off timer and brightens the screen if the device
+     * is not asleep.  This is what happens normally when a key or the touch
+     * screen is pressed or when some other user activity occurs.
+     * This method does not wake up the device if it has been put to sleep.
+     * </p><p>
+     * Requires the {@link android.Manifest.permission#DEVICE_POWER} or
+     * {@link android.Manifest.permission#USER_ACTIVITY} permission.
+     * </p>
+     *
+     * @param when The time of the user activity, in the {@link SystemClock#uptimeMillis()}
+     * time base.  This timestamp is used to correctly order the user activity request with
+     * other power management functions.  It should be set
+     * to the timestamp of the input event that caused the user activity.
+     * @param event The user activity event.
+     * @param flags Optional user activity flags.
+     *
+     * @see #wakeUp
+     * @see #goToSleep
+     *
+     * @hide Requires signature or system permission.
+     */
+    @SystemApi
+    public void userActivity(long when, int event, int flags) {
         try {
-            mService.userActivity(when, USER_ACTIVITY_EVENT_OTHER,
-                    noChangeLights ? USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS : 0);
+            mService.userActivity(when, event, flags);
         } catch (RemoteException e) {
         }
     }
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 7809c71..5194893 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -2408,6 +2408,13 @@
         android:description="@string/permdesc_devicePower"
         android:protectionLevel="signature" />
 
+   <!-- Allows access to the PowerManager.userActivity function.
+   <p>Not for use by third-party applications. @hide @SystemApi -->
+    <permission android:name="android.permission.USER_ACTIVITY"
+        android:label="@string/permlab_userActivity"
+        android:description="@string/permdesc_userActivity"
+        android:protectionLevel="signature|system" />
+
    <!-- @hide Allows low-level access to tun tap driver -->
     <permission android:name="android.permission.NET_TUNNELING"
         android:permissionGroup="android.permission-group.SYSTEM_TOOLS"
diff --git a/core/res/res/values/strings.xml b/core/res/res/values/strings.xml
index b198329..f2e5888 100644
--- a/core/res/res/values/strings.xml
+++ b/core/res/res/values/strings.xml
@@ -1815,6 +1815,11 @@
     <string name="permdesc_devicePower" product="default">Allows the app to turn the phone on or off.</string>
 
     <!-- Title of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
+    <string name="permlab_userActivity">reset display timeout</string>
+    <!-- Description of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
+    <string name="permdesc_userActivity">Allows the app to reset the display timeout.</string>
+
+    <!-- Title of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
     <string name="permlab_factoryTest">run in factory test mode</string>
     <!-- Description of an application permission, listed so the user can choose whether they want to allow the application to do this. -->
     <string name="permdesc_factoryTest" product="tablet">Run as a low-level manufacturer test,