[cogl/cogl-1.12] tex-driver-gles: Fix subregion uploads without GL_EXT_unpack_subimage

[Neil Roberts <nroberts src gnome org>]

commit b3f56ccb4858f4f62ee53c74be1a2233bb608cae
Author: Neil Roberts <neil linux intel com>
Date:   Wed Aug 29 14:10:57 2012 +0100

    tex-driver-gles: Fix subregion uploads without GL_EXT_unpack_subimage
    
    When the GL_EXT_unpack_subimage extension is not available and a
    subregion of a texture is uploaded then it should first copy the
    subregion to a newly allocated bitmap. However it was then later still
    trying to prepare the upload using the original src_x and src_y values
    which would cause an assertion failure. This patch fixes it to just
    reset those to zero if the subregion is first copied.
    
    Reviewed-by: Robert Bragg <robert linux intel com>
    
    (cherry picked from commit 6f9a62db6f846f1d76e3ca16d9d8cdadf82a7009)

 cogl/driver/gles/cogl-texture-driver-gles.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/cogl/driver/gles/cogl-texture-driver-gles.c b/cogl/driver/gles/cogl-texture-driver-gles.c
index d4d2b5d..e19721c 100644
--- a/cogl/driver/gles/cogl-texture-driver-gles.c
+++ b/cogl/driver/gles/cogl-texture-driver-gles.c
@@ -206,6 +206,8 @@ _cogl_texture_driver_upload_subregion_to_gl (CoglContext *ctx,
                                    src_x, src_y,
                                    0, 0, /* dst_x/y */
                                    width, height);
+
+      src_x = src_y = 0;
     }
   else
     slice_bmp = prepare_bitmap_alignment_for_upload (ctx, source_bmp);