Searching for HTML elements works only on first rootPage in E2E testing

Hey guys!

I am facing one issue when I try to run E2E tests. I am using Protractor (5.1.2) for E2E tests.
So everything works fine when I try to search for elements on the rootPage. My tests look like this:
```js
game.navigateToRoot();
game.startGame();
game.playTheGame();
```

Navigation to root works fine, I can normally find the START BUTTON and click on it, which leads me to the GameComponent (I actually change the root like this.nav.setRoot(GameComponent)).
When the game panel is shown, I can not do any HTML selector query, not even (browser.title), because neither one Promise callback is executed. I tried to wait the browser with:
```js
const until = rotractor.ExpectedConditions;
browser.wait(until.presenceOf(game.getFinalResultWrapper()), 5000, 'Element taking too long to appear in the DOM');
```

Here is my game page object where I make HTML queries:
```js
navigateToRoot() {
return browser.get('');
}

startGame() {
const startGameButton = this.getStartGameButton();
this.getStartGameButton().click();
// the NavController's root changes
}

getStartGameButton() {
return $('#start-game');
}

getFinalResultWrapper() {
return $('.level-complete-wrapper');
}

playTheGame() {
// nothing works from now on
const goalWrapper = $('#goal-wrapper');
const until = protractor.ExpectedConditions;
browser.wait(until.presenceOf(goalWrapper), 5000, 'Element taking too long to appear in the DOM');
browser.getTitle().then((title) => {
console.log('title = ', title);
});
$('#goal-wrapper').getSize().then((size) => {
console.log(size);
});
}
```