Evas GL: Skip surface buffers create/allocate for pbuffer with NO_FBO

Summary:
When pbuffer surface is created with EVAS_GL_NO_FBO config,
FBO should not be created/allocated.

src/modules/evas/engines/gl_common/evas_gl_core.c

@@ -1911,7 +1911,10 @@ evgl_pbuffer_surface_create(void *eng_data, Evas_GL_Config *cfg,
    sfc->pbuffer.is_pbuffer = EINA_TRUE;
 
    // If the surface is defined as RGB or RGBA, then create an FBO
-   if (sfc->pbuffer.color_fmt != EVAS_GL_NO_FBO)
+   if (sfc->pbuffer.color_fmt == EVAS_GL_NO_FBO)
+      sfc->buffers_skip_allocate = 1;
+
+   if (!sfc->buffers_skip_allocate)
      {
         // Set the internal config value
         if (!_internal_config_set(eng_data, sfc, cfg))
@@ -2009,21 +2012,27 @@ evgl_surface_destroy(void *eng_data, EVGL_Surface *sfc)
           }
      }
 
-   // Destroy PBuffer surfaces
+   // Destroy PBuffer surface
    if (sfc->pbuffer.native_surface)
      {
         int ret;
         if (dbg) DBG("Surface sfc %p is a pbuffer: %p", sfc, sfc->pbuffer.native_surface);
 
-        ret = evgl_engine->funcs->pbuffer_surface_destroy(eng_data, sfc->pbuffer.native_surface);
+        if (!evgl_engine->funcs->pbuffer_surface_destroy)
-        LKL(evgl_engine->resource_lock);
+          {
-        evgl_engine->surfaces = eina_list_remove(evgl_engine->surfaces, sfc);
+             ERR("Error destroying PBuffer surface");
-        LKU(evgl_engine->resource_lock);
+             return 0;
-        free(sfc);
+          }
 
-        if (!ret) ERR("Engine failed to destroy a PBuffer.");
+        DBG("Destroying PBuffer surface");
+        ret = evgl_engine->funcs->pbuffer_surface_destroy(eng_data, sfc->pbuffer.native_surface);
+
+        if (!ret)
+          {
+             ERR("Engine failed to destroy the PBuffer.");
              return ret;
           }
+     }
 
    if ((rsc->current_ctx) && (rsc->current_ctx->current_sfc == sfc) )
      {
@@ -2309,12 +2318,14 @@ evgl_make_current(void *eng_data, EVGL_Surface *sfc, EVGL_Context *ctx)
           }
      }
 
+   if (!sfc->buffers_skip_allocate)
+     {
         if (!sfc->color_buf && !_surface_buffers_create(sfc))
           {
              ERR("Unable to create specified surfaces.");
              evas_gl_common_error_set(eng_data, EVAS_GL_BAD_ALLOC);
              return 0;
-     };
+          }
 
         // Allocate or free resources depending on what mode (direct of fbo) it's
         // running only if the env var EVAS_GL_DIRECT_MEM_OPT is set.
@@ -2372,6 +2383,7 @@ evgl_make_current(void *eng_data, EVGL_Surface *sfc, EVGL_Context *ctx)
                   sfc->buffers_allocated = 1;
                }
           }
+     }
 
    if (ctx->pixmap_image_supported)
      {

src/modules/evas/engines/gl_common/evas_gl_core_private.h

@@ -123,6 +123,7 @@ struct _EVGL_Surface
    unsigned direct_mem_opt : 1;
 
    // Init Flag
+   unsigned buffers_skip_allocate : 1;
    unsigned buffers_allocated : 1;
 
    void   *cfg;