[metacity/gnome-3-18] frames: use CAIRO_CONTENT_COLOR for cache surface

[Alberts Muktupāvels <muktupavels src gnome org>]

commit cfccb42e58079b7e0bd7e08a1475aa7e58dd9018
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sat Apr 16 16:36:06 2016 +0300

    frames: use CAIRO_CONTENT_COLOR for cache surface

 src/ui/frames.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/ui/frames.c b/src/ui/frames.c
index a5a83e2..c612460 100644
--- a/src/ui/frames.c
+++ b/src/ui/frames.c
@@ -2248,7 +2248,7 @@ generate_pixmap (MetaFrames            *frames,
     return NULL;
 
   result = gdk_window_create_similar_surface (frame->window,
-                                              CAIRO_CONTENT_COLOR_ALPHA,
+                                              CAIRO_CONTENT_COLOR,
                                               rect->width, rect->height);
 
   cr = cairo_create (result);