cogl/winsys: Remove eglGetProcAddress workaround for EGL < 1.5

`eglGetProcAddress()` used to not work for core API in EGL versions
below 1.5. The workaround in place in turn can fail - notably for setups
with a local Mesa build in /usr/local.
EGL 1.5 is almost 10 years old and similar workarounds don't seem to be
in place for toolkits we rely on, notably GTK4. Thus remove it.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3655>

cogl/cogl/cogl-feature-private.c

@@ -52,7 +52,6 @@ _cogl_feature_check (CoglRenderer *renderer,
   const char *suffix = NULL;
   int func_num;
   CoglExtGlesAvailability gles_availability = 0;
-  gboolean in_core;
 
   switch (driver)
     {
@@ -77,7 +76,6 @@ _cogl_feature_check (CoglRenderer *renderer,
       (data->gles_availability & gles_availability))
     {
       suffix = "";
-      in_core = TRUE;
     }
   else
     {
@@ -130,8 +128,6 @@ _cogl_feature_check (CoglRenderer *renderer,
               break;
             }
         }
-
-      in_core = FALSE;
     }
 
   /* If we couldn't find anything that provides the functions then
@@ -148,8 +144,7 @@ _cogl_feature_check (CoglRenderer *renderer,
       full_function_name = g_strconcat (data->functions[func_num].name,
                                         suffix, NULL);
       func = _cogl_renderer_get_proc_address (renderer,
-                                              full_function_name,
+                                              full_function_name);
-                                              in_core);
       g_free (full_function_name);
 
       if (func == NULL)

cogl/cogl/cogl-renderer-private.h

@@ -96,5 +96,4 @@ _cogl_renderer_remove_native_filter (CoglRenderer *renderer,
 
 void *
 _cogl_renderer_get_proc_address (CoglRenderer *renderer,
-                                 const char *name,
+                                 const char   *name);
-                                 gboolean in_core);

cogl/cogl/cogl-renderer.c

@@ -699,12 +699,11 @@ cogl_renderer_get_winsys_id (CoglRenderer *renderer)
 
 void *
 _cogl_renderer_get_proc_address (CoglRenderer *renderer,
-                                 const char *name,
+                                 const char   *name)
-                                 gboolean in_core)
 {
   const CoglWinsysVtable *winsys = _cogl_renderer_get_winsys (renderer);
 
-  return winsys->renderer_get_proc_address (renderer, name, in_core);
+  return winsys->renderer_get_proc_address (renderer, name);
 }
 
 void

cogl/cogl/cogl.c

@@ -59,7 +59,7 @@ cogl_get_proc_address (const char* name)
 {
   _COGL_GET_CONTEXT (ctx, NULL);
 
-  return _cogl_renderer_get_proc_address (ctx->display->renderer, name, FALSE);
+  return _cogl_renderer_get_proc_address (ctx->display->renderer, name);
 }
 
 gboolean

cogl/cogl/driver/gl/gl/cogl-driver-gl.c

@@ -430,16 +430,13 @@ _cogl_driver_update_features (CoglContext *ctx,
      we can expect */
   ctx->glGetString =
     (void *) _cogl_renderer_get_proc_address (ctx->display->renderer,
-                                              "glGetString",
+                                              "glGetString");
-                                              TRUE);
   ctx->glGetStringi =
     (void *) _cogl_renderer_get_proc_address (ctx->display->renderer,
-                                              "glGetStringi",
+                                              "glGetStringi");
-                                              TRUE);
   ctx->glGetIntegerv =
     (void *) _cogl_renderer_get_proc_address (ctx->display->renderer,
-                                              "glGetIntegerv",
+                                              "glGetIntegerv");
-                                              TRUE);
 
   gl_extensions = _cogl_context_get_gl_extensions (ctx);
 

cogl/cogl/driver/gl/gles/cogl-driver-gles.c

@@ -579,12 +579,10 @@ _cogl_driver_update_features (CoglContext *context,
      can expect */
   context->glGetString =
     (void *) _cogl_renderer_get_proc_address (context->display->renderer,
-                                              "glGetString",
+                                              "glGetString");
-                                              TRUE);
   context->glGetStringi =
     (void *) _cogl_renderer_get_proc_address (context->display->renderer,
-                                              "glGetStringi",
+                                              "glGetStringi");
-                                              TRUE);
 
   gl_extensions = _cogl_context_get_gl_extensions (context);
 

cogl/cogl/winsys/cogl-winsys-egl.c

@@ -111,20 +111,9 @@ static const CoglFeatureData winsys_feature_data[] =
 
 static GCallback
 _cogl_winsys_renderer_get_proc_address (CoglRenderer *renderer,
-                                        const char *name,
+                                        const char   *name)
-                                        gboolean in_core)
 {
-  void *ptr = NULL;
+  return eglGetProcAddress (name);
-
-  if (!in_core)
-    ptr = eglGetProcAddress (name);
-
-  /* eglGetProcAddress doesn't support fetching core API so we need to
-     get that separately with GModule */
-  if (ptr == NULL)
-    g_module_symbol (renderer->libgl_module, name, &ptr);
-
-  return ptr;
 }
 
 static void

cogl/cogl/winsys/cogl-winsys-glx.c

@@ -141,15 +141,10 @@ static const CoglFeatureData winsys_feature_data[] =
 
 static GCallback
 _cogl_winsys_renderer_get_proc_address (CoglRenderer *renderer,
-                                        const char *name,
+                                        const char   *name)
-                                        gboolean in_core)
 {
   CoglGLXRenderer *glx_renderer = renderer->winsys;
 
-  /* The GLX_ARB_get_proc_address extension documents that this should
-   * work for core functions too so we don't need to do anything
-   * special with in_core */
-
   return glx_renderer->glXGetProcAddress ((const GLubyte *) name);
 }
 

cogl/cogl/winsys/cogl-winsys-private.h

@@ -68,8 +68,7 @@ typedef struct _CoglWinsysVtable
 
   GCallback
   (*renderer_get_proc_address) (CoglRenderer *renderer,
-                                const char   *name,
+                                const char   *name);
-                                gboolean      in_core);
 
   gboolean
   (*renderer_connect) (CoglRenderer *renderer,