Specify what Faces should do when f:metadata is not a direct child of f:view

[BalusC]

eclipse-ee4j/mojarra#5105 (comment)

There are basically 3 options:

1. ignore f:metadata and log warning
2. use f:metadata but log warning
3. throw exception

[BalusC]

For the record, there are more API concerns about f:metadata in general:

• importConstants should be allowed everywhere, not only in f:metadata #1466
• h:html instead of f:view and/or f:metadata #1683

[BalusC]

Mojarra impl does currently 2 (implemented via https://github.com/eclipse-ee4j/mojarra/pull/5179/files)
MyFaces impl does currently 3.

We should probably set 3 in spec.
cc: @tandraschko

[tandraschko]

should we really do that?
Or isnt it better to implement it not that strict?

[BalusC]

The spec says that it must be a direct child of f:view but the spec does not say what to do otherwise. If we don't throw exception then we basically allow that it doesn't need to be a direct child of f:view and this may cause problems/confusion in long term.

see also eclipse-ee4j/mojarra#5105 (comment)