Name.fromDescendant() should reject empty spaces names

[Jym77]

<a href="#" title="Hello world">
      <span> </span>
</a>

Receives (space) instead of Hello world as a name, because the content takes precedence and Name.fromDescendant() returns Some " " rather than None.
Both Chrome and Firefox give Hello World as name.

• Follow up on DEV-11839
• Follow up on DEV-11885

[kasperisager]

@Jym77 Will you follow up on the Jiras if that isn't already on your list?

[Jym77]

Good call. Forgot these 😓 Will do.