[Merge] lp:~artmello/webbrowser-app/webbrowser-app-private_browsing into lp:webbrowser-app

[Arthur Mello]

There are some issues related with the AP tests:

1. I added a new function on emulators/browser.py to return the NewPrivateTab component. It should be exactly like the one we have for the NewTab component. But it seems that if we extend an QML file without add any property to it, it will report to autopilot as the base component extended (i.e. QQuickItem). If we do add some property, it will report as the filename (i.e. NewPrivateTab). I talked with elopio to check if that could be an issue with autopilot but he told me that this behavior come from the QT. Since I am not sure that should be a bug against upstream (need to discuss why such an implementation with someone more familiar with the code) I changed the emulator to rely on the objectName property which works fine.

2. There is a new AP test to check that "usual" (maybe we need to find a better name) tabs are not being displayed when in private mode. But this test is failing because after we select a open tab (Open tabs view -> click on a tab) the Chrome element is not visible anymore. Not sure if I implemented the test wrong or if it is a real issue.
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https://code.launchpad.net/~artmello/webbrowser-app/webbrowser-app-private_browsing/+merge/257673
Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~artmello/webbrowser-app/webbrowser-app-private_browsing into lp:webbrowser-app.