[gimp] Revert "app: use FAST filter when painting xfer surface"

[Jehan Pagès <jehanp src gnome org>]

commit 21cb905dad8e8ccb95a4a420293102a478b7638e
Author: Jehan <jehan girinstud io>
Date:   Wed Jan 10 03:38:25 2018 +0100

    Revert "app: use FAST filter when painting xfer surface"
    
    This reverts commit 36258a671a04336260b1154128f8ff2cd9b85673.
    This commit was making the rotated canvas rendering quite horrible to
    the point that I think it would make the canvas rotation feature barely
    usable. See bug 759287, comments 13 to 18.
    I think we will need to find other ways to accelerate rendering.
    Compromise on quality is possible, but I think that in this case, this
    was more than just a compromise. It was more like completely abandonning
    quality. We could even see the lines "spiking" while you were rotating!
    Like your drawing was alive!

 app/display/gimpdisplayshell-render.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)
---
diff --git a/app/display/gimpdisplayshell-render.c b/app/display/gimpdisplayshell-render.c
index 167d67a..58e7c23 100644
--- a/app/display/gimpdisplayshell-render.c
+++ b/app/display/gimpdisplayshell-render.c
@@ -333,7 +333,6 @@ gimp_display_shell_render (GimpDisplayShell *shell,
   cairo_set_source_surface (cr, xfer,
                             x - xfer_src_x,
                             y - xfer_src_y);
-  cairo_pattern_set_filter (cairo_get_source (cr), CAIRO_FILTER_FAST);
   cairo_paint (cr);
 
   if (shell->mask)