theme: Include shadow and resize borders

Extend MetaFrameBorders to include shadow and resize borders to
calculate invisible border size. Also added border caching to prevent
recalculating borders on every frame operation.

This is a backport of the following commits from Metacity:
- https://gitlab.gnome.org/GNOME/metacity/-/commit/21e664af
- https://gitlab.gnome.org/GNOME/metacity/-/commit/3c6e269b
- https://gitlab.gnome.org/GNOME/metacity/-/commit/700e87ea

1 files changed, 38 insertions, 8 deletions

diff --git a/src/core/frame.c b/src/core/frame.c
index e1eec2a4..a8ba65c0 100644
--- a/src/core/frame.c
+++ b/src/core/frame.c
@@ -85,6 +85,7 @@ meta_window_ensure_frame (MetaWindow *window)
   frame->mapped = FALSE;
   frame->need_reapply_frame_shape = TRUE;
   frame->is_flashing = FALSE;
+  frame->borders_cached = FALSE;
 
   meta_verbose ("Frame geometry %d,%d  %dx%d\n",
                 frame->rect.x, frame->rect.y,
@@ -302,22 +303,51 @@ meta_frame_get_flags (MetaFrame *frame)
   return flags;
 }
 
+static void
+clear_border (GtkBorder *border)
+{
+  border->left = 0;
+  border->right = 0;
+  border->top = 0;
+  border->bottom = 0;
+}
+
 void
-meta_frame_borders_clear (MetaFrameBorders *self)
+meta_frame_borders_clear (MetaFrameBorders *borders)
 {
-  self->visible.top = self->invisible.top = self->total.top = 0;
-  self->visible.bottom = self->invisible.bottom = self->total.bottom = 0;
-  self->visible.left = self->invisible.left = self->total.left = 0;
-  self->visible.right = self->invisible.right = self->total.right = 0;
+  clear_border (&borders->visible);
+  clear_border (&borders->shadow);
+  clear_border (&borders->resize);
+  clear_border (&borders->invisible);
+  clear_border (&borders->total);
 }
 
 void
 meta_frame_calc_borders (MetaFrame        *frame,
                          MetaFrameBorders *borders)
 {
-  meta_ui_get_frame_borders (frame->window->screen->ui,
-                             frame->xwindow,
-                             borders);
+  if (frame == NULL)
+    {
+      meta_frame_borders_clear (borders);
+    }
+  else
+    {
+      if (!frame->borders_cached)
+        {
+          meta_ui_get_frame_borders (frame->window->screen->ui,
+                                     frame->xwindow,
+                                     &frame->cached_borders);
+          frame->borders_cached = TRUE;
+        }
+
+      *borders = frame->cached_borders;
+   }
+}
+
+void
+meta_frame_clear_cached_borders (MetaFrame *frame)
+{
+  frame->borders_cached = FALSE;
 }
 
 static gboolean