[GFAppBar] clear button does not fire onChanged

[success-0627]

Describe the bug
GFAppBar with searchBar: true, it will show x button when search bar expanded.
If taps this button, search bar input would be cleared with collapsed.
But, even though text changed, no onChanged callback fired.

To Reproduce

GFAppBar(
        title: Text('Search'),
        searchBar: true,
        onChanged: onQueryChanged,
        searchBarColorTheme: Colors.black,
        searchHintStyle: Get.textTheme.headline1.apply(
          color: Colors.black,
        ),
      )

1. tap search magnifying button to expand
2. input something with checking onChanged works
3. tap X right side, to collapse search bar.
4. no onChanged fired
5. repeat step1 again to see what current input is (it would be empty.)

Expected behavior
At step3, we need to get onChanged with empty string
And / Or searchbar event for expand / collapse

[Abishek1997]

Yes, it needs to be fixed. Should be quite easy to do right? Could simply set the searchController to an empty string to reset the searchbar. Please look into it :)

[deepikahr]

@zl910627 Hey, x button is only for search bar expand / collapse purpose.

5.repeat step1 again to see what current input is (it would be empty.), this will be fixed in upcoming version