GLImmediate: Use CL_CHECK_ERROR

This provides a bit more debugging info on MacOS.

source/blender/gpu/opengl/gl_immediate.cc

@@ -30,6 +30,7 @@
 #include "gpu_vertex_format_private.h"
 
 #include "gl_context.hh"
+#include "gl_debug.hh"
 #include "gl_primitive.hh"
 #include "gl_vertex_array.hh"
 
@@ -87,6 +88,8 @@ uchar *GLImmediate::begin()
   /* Does the current buffer have enough room? */
   const size_t available_bytes = buffer_size() - buffer_offset();
 
+  GL_CHECK_ERROR("Immediate Pre-Begin");
+
   glBindBuffer(GL_ARRAY_BUFFER, vbo_id());
 
   bool recreate_buffer = false;
@@ -129,6 +132,7 @@ uchar *GLImmediate::begin()
   }
   void *data = glMapBufferRange(GL_ARRAY_BUFFER, buffer_offset(), bytes_needed, access);
   BLI_assert(data != NULL);
+  GL_CHECK_ERROR("Immediate Post-Begin");
 
   bytes_mapped_ = bytes_needed;
   return (uchar *)data;
@@ -150,6 +154,8 @@ void GLImmediate::end(void)
   }
   glUnmapBuffer(GL_ARRAY_BUFFER);
 
+  GL_CHECK_ERROR("Immediate Post-Unmap");
+
   if (vertex_len > 0) {
     GPU_context_active_get()->state_manager->apply_state();
 
@@ -173,6 +179,8 @@ void GLImmediate::end(void)
      * They are not required so just comment them. (T55722) */
     // glBindBuffer(GL_ARRAY_BUFFER, 0);
     // glBindVertexArray(0);
+
+    GL_CHECK_ERROR("Immediate Post-drawing");
   }
 
   buffer_offset() += buffer_bytes_used;