ClearByTag throws NullReferenceException if there is a notification with a null tag

[timothylcooke]

Library version

2.5.1

Expected behaviour

ClearAll(new ClearByTag(tag)) should handle null as its own value. If you set the tag to clear to be null, it should clear any notifications with a null tag. If you set the tag to clear to an instance of an object, it should leave any notifications with a null tag.

Actual behaviour

If there are any notifications with a null tag, a NullReferenceException is thrown when you call ClearAll(new ClearByTag(tag)).

Steps to reproduce behaviour

See above

Code to reproduce behaviour

See above

[timothylcooke]

Please see my pull request: #102

[rafallopatka]

Nuget package with provided pull request, will be published soon