Problem/Motivation
People might want to render one menu with different markups. That might be necessary in scenarios where there is different styling for menu in mobile and desktop version. There is no theme suggestions to do this and it I didn't find way to add these suggestions in the theme_suggestions_alter so this is not achievable for themers.
Proposed resolution
If menu is rendered in a block create theme suggestions for a menu based on block.
Remaining tasks
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User interface changes
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API changes
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