Warning should be printed when no NoTheme annotation is present

[caalador]

This change is 

[vaadin-bot]

SonarQube analysis reported 23 issues

• 1 critical
• 2 major
• 20 minor

Top 10 extra issues

Note: The following issues were found on lines that were not modified in the pull request. Because these issues can't be reported as line comments, they are summarized here:

1. UIInternals.java#L541: Refactor this code to not nest more than 3 if/for/while/switch/try statements.
2. UIInternals.java#L381: This block of commented-out lines of code should be removed.
3. UIInternals.java#L505: Refactor this method to reduce its Cognitive Complexity from 19 to the 15 allowed.
4. UIInternals.java#L152: Remove this use of "View"; it is deprecated.
5. UIInternals.java#L407: This call to "remove()" may be a performance hot spot if the collection is large.
6. UIInternals.java#L505: Remove this use of "View"; it is deprecated.
7. UIInternals.java#L506: Remove this use of "HasChildView"; it is deprecated.
8. UIInternals.java#L516: Remove this use of "HasChildView"; it is deprecated.
9. UIInternals.java#L516: Remove this use of "View"; it is deprecated.
10. UIInternals.java#L518: Remove this use of "View"; it is deprecated.

[SomeoneToIgnore]

Sorry, have noticed this PR later then #3515
Will close this one.