Problem/Motivation
It became possible to have themes depend on modules in #474684: Allow themes to declare dependencies on modules. In this implementation, the dependee-modules must be enabled in admin/modules before a module-depending theme can be enabled.
Ideally, it would be possible to enable the dependent modules as part of enabling the theme. This was not part of the initial implementation due to the complexities of permissions and confirmation forms when both themes and modules are being enabled.
A partial implementation was added in an earlier iteration of the patch #474684: Allow themes to declare dependencies on modules, once it was apparent that additional validation (including experimental modules) was needed, it was decided that this was better addressed in a followup.
Proposed resolution
Determine how to best implement module-enabling validation in both admin/modules and when enabling module-dependent themes.
Then implement that.
Remaining tasks
Ensure modules that enabled themes depend on cannot be uninstalled.
Handle forms that extend the newly deprecated: ModulesListConfirmForm
User interface changes
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API changes
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Data model changes
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Release notes snippet
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