Bruno Leroux b61335bd3b
Fix DropdownMenu default width does not take label into account (#161219)
## Description

This PR fixes `DropdownMenu` default width when a long label is
provided.

Before:

The width is based on the longest menu item (which can be smaller than
the label):


![image](https://github.com/user-attachments/assets/c8d543a3-12c6-4f8e-ba89-e067a09f8653)

After:

The width also depends on the label width when it is longer than the
menu items.


![image](https://github.com/user-attachments/assets/afde7e35-1da0-46a9-900d-8fd119c30317)


## Related Issue

Fixes [DropdownMenu default width does not take label into
account](https://github.com/flutter/flutter/issues/136678)

## Tests

Adds 2 tests.
2025-02-13 09:48:25 +00:00
..
2025-02-11 23:47:59 +00:00