Ability to use mutable paper-chips without input

In some cases it is useful to be able to programmatically create chip(s) and allowing the user to remove them but without enabling them as input fields (i.e disallowing the user to create chips). I'd like to add this as an optional feature, does this sound like a good idea?

No file or test is named in the issue. Start by locating the paper-chips component and reviewing how it currently creates and removes chips; the desired mode should allow programmatic creation and user removal while disabling user-created chips. Done means the optional behavior is supported without changing the existing input behavior.

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