[iOS] Clear the delegate from ContextActionCell

[rmarinho]

Description of Change

Clear the global closer delegate from ContextActionCell when disposing.

Issues Resolved

• fixes When ListView items is removed and it is empty, Xamarin Forms crash #4314

API Changes

None

Platforms Affected

• iOS

Behavioral/Visual Changes

None

Before/After Screenshots

Not applicable

Testing Procedure

Use issue 4314 gallery page.
Swipe the 2 cell to reveal content actions and delete both items.
Should go the other page without crash

PR Checklist

• Has automated tests
• Rebased on top of the target branch at time of PR
• Changes adhere to coding standard

[rmarinho]

This is the only real change.

[hartez]

So what's all this other stuff?

[hartez]

Just wondering what all the other changes are about.

[hartez]

So what's all this other stuff?

[rmarinho]

Update UITests and another plugin . and of course the test.

[PureWeen]

I re-queue'd the iOS10 test but it looks like the iOS 10 test for this PR failed

System.Exception : Error while performing WaitForElement(Marked("Delete"), "Timed out waiting for element...", null, null, null) ----> System.TimeoutException : Timed out waiting for element...
Stack trace
at Xamarin.UITest.Utils.ErrorReporting.With[T] (System.Func`1[TResult] func, System.Object[] args, System.String memberName) [0x0005b] in <2a16c16730a54859bda72c6bc1c728f7>:0
at Xamarin.UITest.iOS.iOSApp.WaitForElement (System.Func`2[T,TResult] query, System.String timeoutMessage, System.Nullable`1[T] timeout, System.Nullable`1[T] retryFrequency, System.Nullable`1[T] postTimeout) [0x00032] in <2a16c16730a54859bda72c6bc1c728f7>:0
at Xamarin.UITest.iOS.iOSApp.WaitForElement (System.String marked, System.String timeoutMessage, System.Nullable`1[T] timeout, System.Nullable`1[T] retryFrequency, System.Nullable`1[T] postTimeout) [0x0000d] in <2a16c16730a54859bda72c6bc1c728f7>:0
at Xamarin.Forms.Controls.ScreenshotConditionalApp.WaitForElement (System.String marked, System.String timeoutMessage, System.Nullable`1[T] timeout, System.Nullable`1[T] retryFrequency, System.Nullable`1[T] postTimeout) [0x00001] in <e408e636c2ce4f5cbcce37f318de3df5>:0
at Xamarin.Forms.Controls.Issues.Issue4341.Issue4341Test () [0x00072] in <e408e636c2ce4f5cbcce37f318de3df5>:0
--TimeoutException
at Xamarin.UITest.Shared.WaitForHelper.WaitForAny[T] (System.Func`1[TResult] query, System.String timeoutMessage, System.Nullable`1[T] timeout, System.Nullable`1[T] retryFrequency, System.Nullable`1[T] postTimeout) [0x0001d] in <2a16c16730a54859bda72c6bc1c728f7>:0
at Xamarin.UITest.iOS.iOSApp+<>c__DisplayClass65_0.<WaitForElement>b__0 () [0x00054] in <2a16c16730a54859bda72c6bc1c728f7>:0
at Xamarin.UITest.Utils.ErrorReporting.With[T] (System.Func`1[TResult] func, System.Object[] args, System.String memberName) [0x0000e] in <2a16c16730a54859bda72c6bc1c728f7>:0

[PureWeen]

Not sure if we want to open a new issue for this but I'm still getting a NRE in GetContextCell

• delete both rows
• now it goes to success page
• navigate back
• swipe the listview

[rmarinho]

Good catch @PureWeen can you test now?

Thanks