Enables or disables the fixed height mode of @tree_view.
Fixed height mode speeds up #GtkTreeView by assuming that all
rows have the same height.
Only enable this option if all rows are the same height and all
columns are of type %GTK_TREE_VIEW_COLUMN_FIXED.
Enables or disables the fixed height mode of @tree_view. Fixed height mode speeds up #GtkTreeView by assuming that all rows have the same height. Only enable this option if all rows are the same height and all columns are of type %GTK_TREE_VIEW_COLUMN_FIXED.