WebKitGTK 2.39.90 released!

This is a development release leading toward 2.40 series.

Add new JavaScript execution APIs.
Merge functions of registering and unregistering script message handler in GTK4 API.
Mark non-derivable types as final and make instance and class struct declarations private in GTK4 API.
Make favicon and snapshot API use GdkTexture instead of cairo surfaces in GTK4 API.
Fix scrolling after a history navigation with PSON enabled.
Fix criticals from webkitOptionMenuSetEvent when opening any combo box.
Fix large memory allocation when uploading content.
Always update the active uri of WebKitFrame.
Fix several crashes and rendering issues.
Translation updates: Ukrainian.

Thanks to all the contributors who made possible this release.