code: private void refresh() {
          try {
              Canvas canvas = mSurface.lockCanvas(null);
              mWebView.draw(canvas);
              mSurface.unlockCanvasAndPost(canvas);
          } catch (Surface.OutOfResourcesException t) {
              Log.e("GVRWebBoardObject", "lockCanvas failed");
          }
          mSurfaceTexture.updateTexImage();
      }
docs: Draws the {@link WebView} onto {@link #mSurfaceTexture}