Adds untracking for state kGREYPendingViewsToDisappear in greyswizzled_viewDidAppear

[stevenreinisch]

Adds untracking for state kGREYPendingViewsToDisappear if a UIViewController's viewDidAppear has been called.

This is neccessary if the user triggers an incomplete transition between UIViewControllers e.g. in the context of a UIPageViewController. See this example for an explanation:

We show a UIPageViewController with three UIViewControllers VC1, VC2, and VC3.
This is the series of events:

• VC1.viewWillAppear
• VC1.viewDidAppear
• VC1.view is shown to the user
• User performs swipe left
• VC2.viewWillAppear
• VC1.viewWillDisappear
• VC2.viewDidAppear
• VC1.viewDidDisappear
• VC2.view is shown to the user
• User performs swipe left (This swipe does not go far enough to show VC3.view at the end of the swipe)
• VC3.viewWillAppear
• VC2.viewWillDisappear
• VC2.viewWillAppear
• VC2.viewDidAppear
• VC3.viewWillDisappear
• VC3.viewDidDisappear
• VC2.view is shown to the user again

Without this patch, EarlGrey waits for viewDidDisappear: call on VC2 and app state does not become kGREYIdle.
With this patch, at the call of VC2.viewDidAppear state kGREYPendingViewsToDisappear is untracked and app state becomes kGREYIdle.

[tirodkar]

Is this seen in a Page View Controller only? Would be great if we added a test for this as well so we can reproduce this.

[stevenreinisch]

Can you give me hint, at which existing test I can look at to have a starting point?

[tirodkar]

Take a look at one of our view controller specific tests like the UITableView one. You can create a new xib with a Page View Controller and then add some tests that reproduce your issue. To do so,

1. Create the view controller in the TestRig Sources using a xib.
2. Add the view controller to the MainViewController here.
3. Create a test that subclasses FTRBaseIntegrationTest and use the openTestViewNamed: to navigate to your newly created view controller class.
4. In the class, perform the swipes you've mentioned to reproduce the issue.