[cogl] texture: Fix error handling in get_texture_bits_via_offscreen

[Neil Roberts <nroberts src gnome org>]

commit a000189c6844b487786d3599f389fd662feaec3b
Author: Adel Gadllah <adel gadllah gmail com>
Date:   Sat Mar 31 14:29:01 2012 +0200

    texture: Fix error handling in get_texture_bits_via_offscreen
    
    get_texture_bits_via_offscreen does not check the return value of
    cogl_framebuffer_read_pixels_into_bitmap which results into never
    using the fallback path texture_get_cb.
    
    cogl_framebuffer_read_pixels_into_bitmap does not check whether the framebuffer
    is properly allocated though; so fix that as well.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=673137
    
    Reviewed-by: Neil Roberts <neil linux intel com>

 cogl/cogl-framebuffer.c |    3 +++
 cogl/cogl-texture.c     |   11 ++++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)
---
diff --git a/cogl/cogl-framebuffer.c b/cogl/cogl-framebuffer.c
index af95cac..dff08ff 100644
--- a/cogl/cogl-framebuffer.c
+++ b/cogl/cogl-framebuffer.c
@@ -1963,6 +1963,9 @@ cogl_framebuffer_read_pixels_into_bitmap (CoglFramebuffer *framebuffer,
   _COGL_RETURN_VAL_IF_FAIL (source == COGL_READ_PIXELS_COLOR_BUFFER, FALSE);
   _COGL_RETURN_VAL_IF_FAIL (cogl_is_framebuffer (framebuffer), FALSE);
 
+  if (!cogl_framebuffer_allocate (framebuffer, NULL))
+    return FALSE;
+
   ctx = cogl_framebuffer_get_context (framebuffer);
 
   width = cogl_bitmap_get_width (bitmap);
diff --git a/cogl/cogl-texture.c b/cogl/cogl-texture.c
index ab07f91..f44970c 100644
--- a/cogl/cogl-texture.c
+++ b/cogl/cogl-texture.c
@@ -965,6 +965,7 @@ get_texture_bits_via_offscreen (CoglTexture    *texture,
   CoglOffscreen *offscreen;
   CoglFramebuffer *framebuffer;
   CoglBitmap *bitmap;
+  gboolean ret;
 
   _COGL_GET_CONTEXT (ctx, FALSE);
 
@@ -986,15 +987,15 @@ get_texture_bits_via_offscreen (CoglTexture    *texture,
                                      dst_format,
                                      dst_rowstride,
                                      dst_bits);
-  cogl_framebuffer_read_pixels_into_bitmap (framebuffer,
-                                            x, y,
-                                            COGL_READ_PIXELS_COLOR_BUFFER,
-                                            bitmap);
+  ret = cogl_framebuffer_read_pixels_into_bitmap (framebuffer,
+                                                  x, y,
+                                                  COGL_READ_PIXELS_COLOR_BUFFER,
+                                                  bitmap);
   cogl_object_unref (bitmap);
 
   cogl_object_unref (framebuffer);
 
-  return TRUE;
+  return ret;
 }
 
 static gboolean