gtk: Document error quark functions

gtk/css/gtkcsserror.c

@@ -21,12 +21,26 @@
 
 #include "gtkcsserror.h"
 
+/**
+ * gtk_css_parser_error_quark:
+ *
+ * Registers an error quark for CSS parsing errors.
+ *
+ * Returns: the error quark
+ **/
 GQuark
 gtk_css_parser_error_quark (void)
 {
   return g_quark_from_static_string ("gtk-css-parser-error-quark");
 }
 
+/**
+ * gtk_css_parser_warning_quark:
+ *
+ * Registers an error quark for CSS parsing warnings.
+ *
+ * Returns: the warning quark
+ **/
 GQuark
 gtk_css_parser_warning_quark (void)
 {

gtk/gtkbuilder.c

@@ -2953,6 +2953,13 @@ gtk_builder_get_type_from_name (GtkBuilder  *builder,
   return type;
 }
 
+/**
+ * gtk_builder_error_quark:
+ *
+ * Registers an error quark for [class@Gtk.Builder] errors.
+ *
+ * Returns: the error quark
+ **/
 GQuark
 gtk_builder_error_quark (void)
 {

gtk/gtkconstraintlayout.c

@@ -1924,6 +1924,13 @@ attribute_from_name (const char *name)
   return GTK_CONSTRAINT_ATTRIBUTE_NONE;
 }
 
+/**
+ * gtk_constraint_vfl_parser_error_quark:
+ *
+ * Registers an error quark for VFL error parsing.
+ *
+ * Returns: the error quark
+ **/
 GQuark
 gtk_constraint_vfl_parser_error_quark (void)
 {

gtk/gtkdialogerror.c

@@ -20,6 +20,14 @@
 
 #include "gtk/gtkdialogerror.h"
 
+/**
+ * gtk_dialog_error_quark:
+ *
+ * Registers an error quark for an operation that requires a dialog if
+ * necessary.
+ *
+ * Returns: the error quark
+ */
 GQuark
 gtk_dialog_error_quark (void)
 {

gtk/gtkicontheme.c

@@ -2526,7 +2526,13 @@ gtk_icon_theme_lookup_icon (GtkIconTheme       *self,
   return icon;
 }
 
-/* Error quark */
+/**
+ * gtk_icon_theme_error_quark:
+ *
+ * Registers an error quark for [class@Gtk.IconTheme] errors.
+ *
+ * Returns: the error quark
+ **/
 GQuark
 gtk_icon_theme_error_quark (void)
 {

gtk/gtkrecentmanager.c

@@ -243,6 +243,13 @@ has_case_prefix (const char *haystack,
   return *n == '\0';
 }
 
+/**
+ * gtk_recent_manager_error_quark:
+ *
+ * Registers an error quark for [class@RecentManager] errors.
+ *
+ * Returns: the error quark
+ **/
 GQuark
 gtk_recent_manager_error_quark (void)
 {