Gtk vs ViewsGtk

Benefits of ViewsGtk

Better code sharing. For example, don't have to duplicate tab layout or bookmark bar layout code.
- Tab Strip
  - Drawing
  - All the animationy bits
  - Subtle click selection behavior (curved corners)
  - Drag behavior, including dropping of files onto the URL bar
  - Closing behavior
- Bookmarks bar
  - drag & drop behavior, including menus
  - chevron?
Easier for folks to work on both platforms without knowing much about the underlying toolkits.
Don't have to implement ui features twice.

Dialogs
- Native feel layout
- Font size changes (e.g., changing the system font size will apply to our dialogs)
- Better RTL (e.g., https://crbug.com/2822 https://crbug.com/5729 https://crbug.com/6082 https://crbug.com/6103 https://crbug.com/6125 https://crbug.com/8686 https://crbug.com/8649)
Being able to obey the user's system theme
Accessibility for buttons and dialogs (but not for tabstrip and bookmarks)
A better change at good remote X performance?
We still would currently need Pango / Cairo for text layout, so it will be more efficient to just draw that during the Gtk pipeline instead of with Skia.
Gtk widgets will automatically “feel and behave” like Linux. The behavior of our own Views system does not necessarily feel right on Linux.
People working on Windows features don't need to worry about breaking the Linux build.