rendering: Simplify Cairo context usage, remove unneeded calls.

Moved Cairo context usage to Rust, and rearranged ctx setup (position) to happen in one place.

Removed render calls that were overwritten on each draw call anyway.

eek/eek-types.h

@@ -88,5 +88,14 @@ struct transformation {
     gdouble origin_y;
     gdouble scale;
 };
+
+struct squeek_button;
+struct squeek_row;
+
+/// Represents the path to the button within a view
+struct button_place {
+    const struct squeek_row *row;
+    const struct squeek_button *button;
+};
 G_END_DECLS
 #endif  /* EEK_TYPES_H */