android: Drop unused LayerView.Listener.compositorCreated

The method is unused and doesn't do anything. Drop it.

Change-Id: I4076b9d0ca9c58311e67ae40e1b3ba6f5a9c6f30
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/194192
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

android/source/src/java/org/mozilla/gecko/gfx/LayerView.java

@@ -226,7 +226,6 @@ public class LayerView extends FrameLayout {
     }
 
     public interface Listener {
-        void compositorCreated();
         void renderRequested();
         void compositionPauseRequested();
         void surfaceChanged(int width, int height);

android/source/src/java/org/mozilla/gecko/gfx/RenderControllerThread.java

@@ -59,11 +59,6 @@ public class RenderControllerThread extends Thread implements LayerView.Listener
         queue.add(RenderCommand.SHUTDOWN);
     }
 
-    @Override
-    public void compositorCreated() {
-
-    }
-
     @Override
     public void renderRequested() {
         synchronized (this) {