[Vapor] The prop `is` of Vapor components does not support dynamic binding via `v-bind`

[l246804]

Vue version

3.6.0-beta.7

Link to minimal reproduction

https://play.vuejs.org/#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

Steps to reproduce

1. Define the prop for the Vapor component and use it in the template

// Child.vue
withDefaults(defineProps<{
  is: string
}>(), {
  is: 'Child'
})

<template>
  <div>{{ is }}</div>
</template>

2. Use the Vapor component in the parent component and pass :is="'Parent'" via v-bind

3. At this point, the page displays Child and a warning is shown indicating that a required prop is missing. The v-bind passing method is supported in VDOM mode.

What is expected?

1. When passing the is prop to a Vapor component via v-bind (e.g., :is="'Parent'"), the component should correctly receive and render the dynamically bound value (Parent), instead of falling back to the default value (Child).
2. No false warning about a "required prop missing" should be thrown when the is prop is passed via v-bind (consistent with the behavior in VDOM mode).

What is actually happening?

1. When passing the is prop to the Vapor component via v-bind (i.e., :is="'Parent'"), the component does not receive the dynamically bound value Parent — instead, it renders the default value Child (defined via withDefaults).
2. A false warning is thrown in the console indicating that the required is prop is missing, even though the prop is explicitly passed via v-bind.
3. This behavior is inconsistent with VDOM mode (where v-bind for the is prop works as expected, with no false warnings).

System Info

Any additional comments?

No response

[edison1105]

fixed via #14491