Moves bookmark item width into the state

[NejcZdovc]

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.

Resolves #9517

Auditors: @bsclifton @bridiver @ayumi

Test Plan:

Reviewer Checklist:

Tests

• Adequate test coverage exists to prevent regressions
• Tests should be independent and work correctly when run individually or as a suite ref
• New files have MPL2 license header

[NejcZdovc]

TODO

• add updater, so that update from x to 0.19 will automatically update state
• recalculate all bookmarks when you switch bookmarks toolbar display setting
• calculate when importing bookmarks
• calculate when syncing

[NejcZdovc]

closing for now, because we need to find another way to calculate font length