Add ability to re-enable webview optimizations

src/android/BackgroundModeExt.java

@@ -101,6 +101,9 @@ public class BackgroundModeExt extends CordovaPlugin {
             case "webview":
                 disableWebViewOptimizations();
                 break;
+            case "enableWebview":
+                enableWebViewOptimizations();
+                break;
             case "appstart":
                 openAppStart(args.opt(0));
                 break;
@@ -196,6 +199,31 @@ public class BackgroundModeExt extends CordovaPlugin {
         thread.start();
     }
 
+    private void enableWebViewOptimizations() {
+        Thread thread = new Thread(){
+            public void run() {
+                try {
+                    Thread.sleep(1000);
+                    getApp().runOnUiThread(() -> {
+                        View view = webView.getView();
+
+                        try {
+                            Class.forName("org.crosswalk.engine.XWalkCordovaView")
+                                 .getMethod("onHide")
+                                 .invoke(view);
+                        } catch (Exception e){
+                            view.dispatchWindowVisibilityChanged(View.GONE);
+                        }
+                    });
+                } catch (InterruptedException e) {
+                    // do nothing
+                }
+            }
+        };
+
+        thread.start();
+    }
+
     /**
      * Disables battery optimizations for the app.
      * Requires permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS to function.

www/background-mode.js

@@ -164,6 +164,14 @@ exports.disableWebViewOptimizations = function()
     }
 };
 
+exports.enableWebViewOptimizations = function()
+{
+    if (this._isAndroid)
+    {
+        cordova.exec(null, null, 'BackgroundModeExt', 'enableWebview', []);
+    }
+};
+
 /**
  * Disables battery optimazation mode for the app.
  *