tests/cogl: Migrate offscreen test

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2555>

cogl/tests/conform/meson.build

@@ -1,6 +1,5 @@
 cogl_test_conformance_sources = [
   'test-conform-main.c',
-  'test-offscreen.c',
   'test-journal.c',
   'test-primitive.c',
   'test-sparse-pipeline.c',

cogl/tests/conform/test-conform-main.c

@@ -80,7 +80,6 @@ main (int argc, char **argv)
 
   ADD_TEST (test_primitive, 0, 0);
 
-  ADD_TEST (test_offscreen, 0, 0);
   ADD_TEST (test_journal_unref_flush, 0, 0);
   ADD_TEST (test_framebuffer_get_bits,
             TEST_REQUIREMENT_GL,

cogl/tests/conform/test-declarations.h

@@ -13,7 +13,6 @@ void test_read_texture_formats (void);
 void test_write_texture_formats (void);
 void test_alpha_textures (void);
 void test_primitive (void);
-void test_offscreen (void);
 void test_journal_unref_flush (void);
 void test_framebuffer_get_bits (void);
 void test_point_size (void);

src/tests/cogl/conform/meson.build

@@ -14,6 +14,7 @@ cogl_tests = [
   'test-wrap-modes',
   'test-sub-texture',
   'test-custom-attributes',
+  'test-offscreen',
 ]
 
 cogl_test_conformance_includes = [

src/tests/cogl/conform/test-offscreen.c

@@ -2,8 +2,7 @@
 
 #include <cogl/cogl.h>
 
-#include "test-declarations.h"
-#include "test-utils.h"
+#include "tests/cogl-test-utils.h"
 
 #define RED 0
 #define GREEN 1
@@ -192,7 +191,7 @@ test_flush (TestState *state)
   cogl_object_unref (pipeline);
 }
 
-void
+static void
 test_offscreen (void)
 {
   TestState state;
@@ -206,3 +205,7 @@ test_offscreen (void)
   if (cogl_test_verbose ())
     g_print ("OK\n");
 }
+
+COGL_TEST_SUITE (
+  g_test_add_func ("/offscreen", test_offscreen);
+)