feat(warn): Warn component names hyphenated into reserved names, fix #8025

[hatashiro]

Currently, component names like 'Map' is silently ignored, because they translated into reserved names but the component names are not exactly the same as the reserved names. The component names, thus, should be hyphenated before checking if reserved.

Resolve #8025.

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• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
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Does this PR introduce a breaking change? (check one)

• Yes
• No

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Other information:

The reason of using hyphenate() instead of .toLowerCase() is that we should allow a name like MaP, as it is shown as ma-p in template and thus a valid component name.

[HerringtonDarkholme]

Vue community has at least one popular library that uses Input or Select as component name. Say vuejs/vetur#303 and vuejs/eslint-plugin-vue#181 .

I don't know if it will be an annoying warning. cc @icarusion

[hatashiro]

Didn’t know that these child components actually work when we use the capitalized name as it is. But I think it’s really ambiguous, because, as described in #8025, we are sometimes not sure if a name is reserved and should be used in case-sensitive way. I think it’s generally good to warn users when they’re using CamelCased reserved names.