Improve documents: [content scripts] dynamic declarations with dynamic host permissions

[hanguokai]

Related documents that need to be improved:

• https://developer.chrome.com/docs/extensions/mv3/content_scripts/#dynamic-declarative
• https://developer.chrome.com/docs/extensions/reference/scripting/#method-registerContentScripts

See this discussion: scripting.registerContentScripts() when there are no host permissions

There are documents about "Inject content scripts with dynamic declarations". But the doc doesn't say the relationship between registerContentScripts() and host permissions. In fact, if there is no host permissions, registerContentScripts() still execute successfully, but no content scripts will be injected to pages. Therefore, to use dynamic declarations correctly, it needs to cooperate with chrome.permissions.contains() and chrome.permissions.request().

[dstmarthe]

Thanks for raising this. We’re moving to a new platform and so we’ll fix this over there. I’ve moved the issue to our new tracker and you can see it at https://issuetracker.google.com/issues/311090117