Redraw all windows earlier in power on sequence.

Send a message to all windows to redraw before notifying
PhoneWindowManager of screen on. This minimizes the delay in
screen update that causes the keyguard clock to display the old time
before displaying the current time.

Fixes bug 6381021.

Change-Id: Ida7071e7dac2284540f101c5d004511b52133b91

Author: Craig Mautner

policy/src/com/android/internal/policy/impl/PhoneWindowManager.java

@@ -3506,6 +3506,10 @@ public void screenTurningOn(final ScreenOnListener screenOnListener) {
         }
         if (screenOnListener != null) {
             if (mKeyguardMediator != null) {
+                try {
+                    mWindowManager.setEventDispatching(true);
+                } catch (RemoteException unhandled) {
+                }
                 mKeyguardMediator.onScreenTurnedOn(new KeyguardViewManager.ShowListener() {
                     @Override public void onShown(IBinder windowToken) {
                         if (windowToken != null) {

services/java/com/android/server/wm/WindowManagerService.java

@@ -6621,15 +6621,14 @@ public void resumeKeyDispatching(IBinder _token) {
 
     public void setEventDispatching(boolean enabled) {
         if (!checkCallingPermission(android.Manifest.permission.MANAGE_APP_TOKENS,
-                "resumeKeyDispatching()")) {
+                "setEventDispatching()")) {
             throw new SecurityException("Requires MANAGE_APP_TOKENS permission");
         }
 
         synchronized (mWindowMap) {
             mInputMonitor.setEventDispatchingLw(enabled);
+            sendScreenStatusToClientsLocked();
         }
-
-        sendScreenStatusToClients();
     }
 
     public IBinder getFocusedWindowClientToken() {
@@ -6735,7 +6734,7 @@ public void systemReady() {
         mPolicy.systemReady();
     }
 
-    private void sendScreenStatusToClients() {
+    private void sendScreenStatusToClientsLocked() {
         final ArrayList<WindowState> windows = mWindows;
         final int count = windows.size();
         boolean on = mPowerManager.isScreenOn();