feat: add `WebView::focus_parent` method.

[huacnlee]

The blur method need in some case, for example the WebView is a child in window (The WebView is not full size in the Window). When we click the main area, we want the WebView to lose the focus handle.

• [x] WKWebView
• [x] WebView2 (need to test)
• [ ] WebkitGTK, Android (I don't find the API doc how to implement it, so keep is do nothing.)

I use this for add Wry into GPUI, here is the bug fix:

https://github.com/huacnlee/gpui-component/pull/320

Before

https://github.com/user-attachments/assets/cc614334-47fe-4722-8745-aea783fbab4a

After

After called cx.blur on mouse click outside the WebView area.

On macOS, now the IME bug is gone.

https://github.com/user-attachments/assets/363bb016-229f-4766-84f7-6a4838e490bf

[huacnlee]

Windows as test passed.

https://github.com/user-attachments/assets/320c5c1c-cfac-4165-af8a-bc9708952460

[github-actions[bot]]

Package Changes Through b6a2ba6b91e341cc95258524f430506a0b278c07

There are 1 changes which include wry with patch

Planned Package Versions

The following package releases are the planned based on the context of changes in this pull request. | package | current | next | |----|----|----| | wry | 0.46.0 | 0.46.1 |

Add another change file through the GitHub UI by following this link.

---

Read about change files or the docs at github.com/jbolda/covector

[huacnlee]

I can rename it do focus_parent.

This should be provided a method from wry, because I can't get the parent view in outside.

[amrbashir]

I guess we can include it then.

[amrbashir]

WebkitGTK, Android (I don't find the API doc how to implement it, so keep is do nothing.)

Android can be documented as unsupported. As for webkit2gtk, try calling widget.parent_window() and then call focus on it.

[huacnlee]

Can I just keep Android unsupport? the reason is:

1. I found that the focus method also not did supported in Android.
2. I don't know how to test it, to make sure the change is correct.