[cogl/cogl-1.18] framebuffer: NOP _set_color_mask if mask isn't changing

[Robert Bragg <rbragg src gnome org>]

commit c1724eff6096033de4931fbc03ead14c71f252f5
Author: Robert Bragg <robert linux intel com>
Date:   Tue Oct 15 14:04:12 2013 +0100

    framebuffer: NOP _set_color_mask if mask isn't changing
    
    This makes cogl_framebuffer_set_color_mask immediately bail out if the
    given mask equals the framebuffer's current mask, since the cost of
    flushing the journal and flushing the gl state will hugely outweigh the
    cost of the check.
    
    Reviewed-by: Neil Roberts <neil linux intel com>
    (cherry picked from commit 925174d99df7f1f4b11098e748bcc23eaa396a21)

 cogl/cogl-framebuffer.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/cogl/cogl-framebuffer.c b/cogl/cogl-framebuffer.c
index 6b916cc..20863ff 100644
--- a/cogl/cogl-framebuffer.c
+++ b/cogl/cogl-framebuffer.c
@@ -1248,6 +1248,9 @@ void
 cogl_framebuffer_set_color_mask (CoglFramebuffer *framebuffer,
                                  CoglColorMask color_mask)
 {
+  if (framebuffer->color_mask == color_mask)
+    return;
+
   /* XXX: Currently color mask changes don't go through the journal */
   _cogl_framebuffer_flush_journal (framebuffer);