Fix screen timeout determination for starting dream.

It turns out OFF_BECAUSE_OF_TIMEOUT is not the best indicator
of actual screen timeout.

For example, it is the reason passed down when acquiring a wake lock.
This was causing us to launch Dreams in the wrong situations, and
deadlocking on calls to WindowManager.

This fix simply adds an additional check ensuring the intention is to
turn the screen off.

Change-Id: If8adff446b5b1fcb19424b45878b75bfd0552b90

Author: John Spurlock

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

@@ -1830,8 +1830,8 @@ private void setPowerState(int newState, boolean noChangeLights, int reason)
 
             final boolean stateChanged = mPowerState != newState;
 
-            if (stateChanged && reason == WindowManagerPolicy.OFF_BECAUSE_OF_TIMEOUT) {
-                if (mPolicy != null && mPolicy.isScreenSaverEnabled() && mIsPowered) {
+            if (stateChanged && !newScreenOn && reason == WindowManagerPolicy.OFF_BECAUSE_OF_TIMEOUT) {
+                if (mPolicy != null && mIsPowered && mPolicy.isScreenSaverEnabled()) {
                     if (DEBUG) {
                         Slog.d(TAG, "setPowerState: running screen saver instead of turning off screen");
                     }