Also fix KEYCODE in JuceAppActivity when disabling the screensaver on android

modules/juce_core/native/java/JuceAppActivity.java

@@ -297,7 +297,7 @@ public class JuceAppActivity   extends Activity
 
                         try
                         {
-                            instrumentation.sendKeyDownUpSync (KeyEvent.KEYCODE_BREAK);
+                            instrumentation.sendKeyDownUpSync (KeyEvent.KEYCODE_UNKNOWN);
                         }
                         catch (Exception e)
                         {