Wayland: make sure wl_surface_frame() is followed by wl_surface_commit().

src/drivers/Wayland/Fl_Wayland_Graphics_Driver.cxx

@@ -26,6 +26,7 @@
 #include <sys/mman.h>
 #include <unistd.h> // for close()
 #include <errno.h>
+#include <string.h> // for strerror()
 
 extern unsigned fl_cmap[256]; // defined in fl_color.cxx
 

src/drivers/Wayland/Fl_Wayland_Screen_Driver.cxx

@@ -41,6 +41,7 @@
 #include <sys/mman.h>
 #include <poll.h>
 #include <errno.h>
+#include <string.h> // for strerror()
 extern "C" {
   bool libdecor_get_cursor_settings(char **theme, int *size);
 }

src/drivers/Wayland/Fl_Wayland_Window_Driver.cxx

@@ -431,6 +431,7 @@ void Fl_Wayland_Window_Driver::flush() {
   Fl_Window_Driver::flush();
   Fl_Wayland_Window_Driver::in_flush = false;
 
+  window->buffer->draw_buffer_needs_commit = true;
   wl_surface_frame(window->wl_surface);
   Fl_Wayland_Graphics_Driver::buffer_commit(window);
 }