[metacity/argb-frame: 6/7] frames: use CAIRO_CONTENT_COLOR_ALPHA

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 0b2f5ad0a2f30726ac0dc59aa59f7f513e91c832
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Aug 22 12:25:44 2019 +0300

    frames: use CAIRO_CONTENT_COLOR_ALPHA
    
    And do not fill surface with opaque black (the default source
    pattern).

 src/ui/frames.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)
---
diff --git a/src/ui/frames.c b/src/ui/frames.c
index 1a661d85..44c4a6ba 100644
--- a/src/ui/frames.c
+++ b/src/ui/frames.c
@@ -2250,14 +2250,12 @@ generate_pixmap (MetaFrames            *frames,
     return NULL;
 
   result = gdk_window_create_similar_surface (frame->window,
-                                              CAIRO_CONTENT_COLOR,
+                                              CAIRO_CONTENT_COLOR_ALPHA,
                                               rect->width, rect->height);
 
   cr = cairo_create (result);
   cairo_translate (cr, -rect->x, -rect->y);
 
-  cairo_paint (cr);
-
   meta_frames_paint (frames, frame, cr);
 
   cairo_destroy (cr);