[mutter] clutter/stage: Fix framebuffer capture origin offset (again)

[Rui Matos <rtcm src gnome org>]

commit fc8de3d0c85f14078db330751c04940edcf4e118
Author: Rui Matos <tiagomatos gmail com>
Date:   Wed Sep 21 15:06:08 2016 +0200

    clutter/stage: Fix framebuffer capture origin offset (again)
    
    Commit 5fbb4793017b1891f0de4720a9793e8cfc1c8483 was wrong too. What we
    really want to do here is getting view relative coordinates given the
    view's and the rectangle's global coordinates so we need to subtract
    the view's origin from the rectangle's.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=771502

 clutter/clutter/clutter-stage.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/clutter/clutter/clutter-stage.c b/clutter/clutter/clutter-stage.c
index 1d2c0bc..21968b9 100644
--- a/clutter/clutter/clutter-stage.c
+++ b/clutter/clutter/clutter-stage.c
@@ -4712,8 +4712,8 @@ capture_view (ClutterStage          *stage,
   clutter_stage_view_get_layout (view, &view_layout);
 
   cogl_framebuffer_read_pixels_into_bitmap (framebuffer,
-                                            view_layout.x + rect->x,
-                                            view_layout.y + rect->y,
+                                            rect->x - view_layout.x,
+                                            rect->y - view_layout.y,
                                             COGL_READ_PIXELS_COLOR_BUFFER,
                                             bitmap);