[gitg] Fix documentation generation

[Iñigo Martínez <inigomartinez src gnome org>]

commit 5b6d2cd50292673d0ced5014e5e5f50c90167028
Author: Iñigo Martínez <inigomartinez gmail com>
Date:   Mon Dec 11 15:18:14 2017 +0100

    Fix documentation generation
    
    The GitgExt.Activity class is not properly documented due to
    missing @return taglet.
    
    This patchs adds the missing taglet allowing documentation to
    be generated properly.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=791480

 libgitg-ext/gitg-ext-activity.vala |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)
---
diff --git a/libgitg-ext/gitg-ext-activity.vala b/libgitg-ext/gitg-ext-activity.vala
index ffe68c2..23528f0 100644
--- a/libgitg-ext/gitg-ext-activity.vala
+++ b/libgitg-ext/gitg-ext-activity.vala
@@ -34,9 +34,8 @@ public interface Activity : Object, UIElement
         *
         * @param action the action.
         *
-        * Returns %TRUE if the activity is the default activity for @action,
-        * %FALSE otherwise.
-        *
+        * @return true if the activity is the default activity for @action,
+        *         false otherwise.
         */
        public virtual bool is_default_for(string action)
        {