Make sure surface control is really valid before giving it to client am: 7581cddf

                    }

                    result |= RELAYOUT_RES_SURFACE_CHANGED;

                }

                final WindowSurfaceController surfaceController = winAnimator.mSurfaceController;

                if (viewVisibility == View.VISIBLE && surfaceController != null) {

                if (viewVisibility == View.VISIBLE && winAnimator.hasSurface()) {

                    // We already told the client to go invisible, but the message may not be

                    // handled yet, or it might want to draw a last frame. If we already have a

                    // surface, let the client use that, but don't create new surface at this point.

                    surfaceController.getSurface(outSurface);

                    winAnimator.mSurfaceController.getSurface(outSurface);

                } else {

                    if (DEBUG_VISIBILITY) Slog.i(TAG_WM, "Releasing surface in: " + win);