[5.24][kcms/style] Consider GTK theme setting when computing default state
The GTK theme name is not managed by KConfigXT, we need to manually track that when determining whether the Defaults button is enabled
(cherry picked from commit 05f21f51)
The GTK theme name is not managed by KConfigXT, we need to manually track that when determining whether the Defaults button is enabled
(cherry picked from commit 05f21f51)