PropertyTabAttribute.Equals(PropertyTabAttribute other) should likely accept null

[krwq]

Found during adding nullable annotations to TypeConverter (#54961).

Most likely the signature for this method should look like:

public bool Equals([NotNullWhen(true)] PropertyTabAttribute? other)

but currently it will throw NRE as it accesses members without any null checks

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Issue Details

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Found during adding nullable annotations to TypeConverter (#54961).

Most likely the signature for this method should look like:

public bool Equals([NotNullWhen(true)] PropertyTabAttribute? other)

but currently it will throw NRE as it accesses members without any null checks

Author:	krwq
Assignees:	-
Labels:	area-System.ComponentModel
Milestone:	-