Add a temporary hack to report screen on while dozing.

The window manager and view hierarchy currently disable all drawing
when PowerManager.isScreenOn() returns false so no drawing occurs
while dozing.  This will be fixed in a future patch to take the
display blanking state into account correctly.

This patch is a workaround to unblock development in the meantime.

Bug: 13133142
Change-Id: I2dc0b422c77285e657d73adca2606aa68264d987

services/core/java/com/android/server/power/PowerManagerService.java

@@ -1802,7 +1802,12 @@ public final class PowerManagerService extends com.android.server.SystemService
 
     private boolean isScreenOnInternal() {
         synchronized (mLock) {
-            return isScreenOnLocked();
+            // XXX This is a temporary hack to let certain parts of the system pretend the
+            // screen is still on even when dozing and we would normally want to report
+            // screen off.  Will be removed when the window manager is modified to use
+            // the true blanking state of the display.
+            return isScreenOnLocked()
+                    || mWakefulness == WAKEFULNESS_DOZING;
         }
     }