[mutter] clutter/actor: Respect CONTENT_SIZE request mode in get_preferred_* APIs

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit f2f89d9b46e655e65dd5e0cbcfe1d71597f673b8
Author: Jonas Dreßler <verdre v0yd nl>
Date:   Sat Oct 26 09:44:01 2019 +0200

    clutter/actor: Respect CONTENT_SIZE request mode in get_preferred_* APIs
    
    Right now the CONTENT_SIZE request mode for a ClutterActor is only
    respected by `clutter_actor_get_preferred_size()`, but not by
    `get_preferred_width()` and `get_preferred_height()`. Those simply try
    to ask the layout manager and will return [0, 0] for actors without
    children. So be consistent and also return the content size in those two
    functions.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/1019

 clutter/clutter/clutter-actor.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)
---
diff --git a/clutter/clutter/clutter-actor.c b/clutter/clutter/clutter-actor.c
index 79a92196a..d711f0607 100644
--- a/clutter/clutter/clutter-actor.c
+++ b/clutter/clutter/clutter-actor.c
@@ -9725,6 +9725,23 @@ clutter_actor_get_preferred_width (ClutterActor *self,
       return;
     }
 
+  /* if the request mode is CONTENT_SIZE we simply return the content width */
+  if (priv->request_mode == CLUTTER_REQUEST_CONTENT_SIZE)
+    {
+      float content_width = 0.f;
+
+      if (priv->content != NULL)
+        clutter_content_get_preferred_size (priv->content, &content_width, NULL);
+
+      if (min_width_p != NULL)
+        *min_width_p = content_width;
+
+      if (natural_width_p != NULL)
+        *natural_width_p = content_width;
+
+      return;
+    }
+
   CLUTTER_SET_PRIVATE_FLAGS (self, CLUTTER_IN_PREF_WIDTH);
 
   /* the remaining cases are:
@@ -9873,6 +9890,23 @@ clutter_actor_get_preferred_height (ClutterActor *self,
       return;
     }
 
+  /* if the request mode is CONTENT_SIZE we simply return the content height */
+  if (priv->request_mode == CLUTTER_REQUEST_CONTENT_SIZE)
+    {
+      float content_height = 0.f;
+
+      if (priv->content != NULL)
+        clutter_content_get_preferred_size (priv->content, NULL, &content_height);
+
+      if (min_height_p != NULL)
+        *min_height_p = content_height;
+
+      if (natural_height_p != NULL)
+        *natural_height_p = content_height;
+
+      return;
+    }
+
   CLUTTER_SET_PRIVATE_FLAGS (self, CLUTTER_IN_PREF_HEIGHT);
 
   /* the remaining cases are: