Remove presumably-useless? serializability checks

[madelson]

Came across this when reading through the code during a debug session. Most of these checks (including the similar ones in ListDictionaryInternal) were removed some time ago, but this one wasn't behind a #if, so perhaps there's a good reason to keep it around.

Figured I'd file a PR just in case there was interest in cleaning this up.

From a quick search it appears this may be the last usage of SR.Argument_NotSerializable, so possibly that could be removed too if this is accepted.

[ghost]

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Issue Details

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Came across this when reading through the code during a debug session. Most of these checks (including the similar ones in ListDictionaryInternal) were removed some time ago, but this one wasn't behind a #if, so perhaps there's a good reason to keep it around.

Figured I'd file a PR just in case there was interest in cleaning this up.

From a quick search it appears this may be the last usage of SR.Argument_NotSerializable, so possibly that could be removed too if this is accepted.

Author:	madelson
Assignees:	-
Labels:	area-System.Collections, community-contribution
Milestone:	-

[StephenMolloy]

This is really more @GrabYourPitchforks's call. I don't have a problem with removing these checks. It makes this consistent with ListDictionaryInternal which should be the goal since they are used as complements.

However, there is one of two issues with this proposed change.

1. The same checks should be removed from this[]{ set; } - again, to be consistent with ListDictionaryInternal.

or

2. These checks should stay in EmptyReadOnlyDictionaryInternal and be added back to ListDictionaryInternal, because Exception and it's data container are serializable and these exceptions should probably be thrown when adding unserializable data rather than at serialization time. (They used to be part of ListDictionaryInternal hidden behind an #if some time ago.)

But whichever resolution is decided, I think the important thing is to keep consistent behavior between the two collection types - which are only used for Exception data as far as I can tell.

[ghost]

Tagging subscribers to this area: @dotnet/area-system-runtime
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Came across this when reading through the code during a debug session. Most of these checks (including the similar ones in ListDictionaryInternal) were removed some time ago, but this one wasn't behind a #if, so perhaps there's a good reason to keep it around.

Figured I'd file a PR just in case there was interest in cleaning this up.

From a quick search it appears this may be the last usage of SR.Argument_NotSerializable, so possibly that could be removed too if this is accepted.

Author:	madelson
Assignees:	-
Labels:	area-Serialization, area-System.Runtime, community-contribution
Milestone:	-

[jkotas]

added back to ListDictionaryInternal, because Exception

This would be a breaking change. I do not think we can justify making this breaking change now that these checks were removed years ago.

[jkotas]

Thanks