h:button,h:commandButton: generate an HTML BUTTON if there is content.

Visual representations of buttons appear to be presently crippled by the inability to include mixed content, e.g. a standard with an image and a label. h:button and h:commandButton are presently specified only to render as an INPUT with an appropriate type. If there is content inside the tag could they please render as a BUTTON instead? so it works intuitively as expected? Or some other feature to the same end?
#### Environment
All
#### Affected Versions
[2.2 Sprint 8]

Start at the rendering entry points for h:button and h:commandButton and inspect their current HTML output, then review the Jakarta Faces component and renderer expectations for content-bearing buttons. Done should be a documented, tested behavior that renders a BUTTON when content is present while retaining the existing behavior where appropriate.

Written by the indexing model from the issue text.