Fix GVariantBuilder leaks

When using g_variant_builder_new(), we must call
g_variant_builder_unref() to free it:
"You should call g_variant_builder_unref() on the return value when it
is no longer needed. The memory will not be automatically freed by any
other call.

In most cases it is easier to place a GVariantBuilder directly on the
stack of the calling function and initialise it with
g_variant_builder_init()."

One of these leaks showed up in valgrind as:
==20702== 16,416 bytes in 114 blocks are definitely lost in loss record 2,114 of 2,115
==20702==    at 0x4A0645D: malloc (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==20702==    by 0x56EDDF2: g_malloc (gmem.c:97)
==20702==    by 0x570691C: g_slice_alloc (gslice.c:1007)
==20702==    by 0x5729743: g_variant_builder_new (gvariant.c:3169)
==20702==    by 0x40297B: ibus_config_dconf_get_values (config.c:413)
==20702==    by 0x4E44FF2: ibus_config_service_service_method_call (ibusconfigservice.c:214)
==20702==    by 0x4E33249: ibus_service_service_method_call_cb (ibusservice.c:395)
==20702==    by 0x51880D8: call_in_idle_cb (gdbusconnection.c:4875)
==20702==    by 0x56E81D7: g_idle_dispatch (gmain.c:5319)
==20702==    by 0x56E58F1: g_main_dispatch (gmain.c:3064)
==20702==    by 0x56E6667: g_main_context_dispatch (gmain.c:3663)
==20702==    by 0x56E6859: g_main_context_iterate (gmain.c:3734)

6 files changed, 17 insertions, 10 deletions

diff --git a/bus/ibusimpl.c b/bus/ibusimpl.c
index eec6da3f..97f36023 100644
--- a/bus/ibusimpl.c
+++ b/bus/ibusimpl.c
@@ -2033,6 +2033,7 @@ bus_ibus_impl_property_changed (BusIBusImpl *service,
                                             "org.freedesktop.IBus",
                                             builder,
                                             NULL));
+    g_variant_builder_unref (builder);
 
     bus_dbus_impl_dispatch_message_by_rule (BUS_DEFAULT_DBUS, message, NULL);
     g_object_unref (message);
diff --git a/bus/inputcontext.c b/bus/inputcontext.c
index 9cbd2eca..b7e1ff8f 100644
--- a/bus/inputcontext.c
+++ b/bus/inputcontext.c
@@ -710,14 +710,15 @@ bus_input_context_property_changed (BusInputContext *context,
     if (context->connection == NULL)
         return TRUE;
 
-    GVariantBuilder *builder = g_variant_builder_new (G_VARIANT_TYPE_ARRAY);
-    g_variant_builder_add (builder, "{sv}", property_name, value);
+    GVariantBuilder builder;
+    g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
+    g_variant_builder_add (&builder, "{sv}", property_name, value);
     return bus_input_context_send_signal (context,
                                           "org.freedesktop.DBus.Properties",
                                           "PropertiesChanged",
                                           g_variant_new ("(sa{sv}as)",
                                                          "org.freedesktop.IBus",
-                                                         builder,
+                                                         &builder,
                                                          NULL),
                                           error);
 }
diff --git a/conf/dconf/config.c b/conf/dconf/config.c
index 0dd317ae..f0e195b3 100644
--- a/conf/dconf/config.c
+++ b/conf/dconf/config.c
@@ -399,7 +399,7 @@ ibus_config_dconf_get_values (IBusConfigService *config,
     gchar *dir, *gdir;
     gint len;
     gchar **entries, **p;
-    GVariantBuilder *builder;
+    GVariantBuilder builder;
     gboolean preserve_name;
 
     dir = g_strdup_printf (DCONF_PREFIX"/%s/", section);
@@ -409,7 +409,7 @@ ibus_config_dconf_get_values (IBusConfigService *config,
     preserve_name = _has_prefixes (gdir, dconf->preserve_name_prefixes);
 
     entries = dconf_client_list (client, gdir, &len);
-    builder = g_variant_builder_new (G_VARIANT_TYPE ("a{sv}"));
+    g_variant_builder_init (&builder, G_VARIANT_TYPE ("a{sv}"));
     for (p = entries; *p != NULL; p++) {
         gchar *gkey = g_strconcat (gdir, *p, NULL);
         GVariant *value = dconf_client_read (client, gkey);
@@ -419,7 +419,7 @@ ibus_config_dconf_get_values (IBusConfigService *config,
             if (!preserve_name) {
                 name = _from_gsettings_name (*p);
             }
-            g_variant_builder_add (builder, "{sv}", name, value);
+            g_variant_builder_add (&builder, "{sv}", name, value);
             if (name != *p) {
                 g_free (name);
             }
@@ -429,7 +429,7 @@ ibus_config_dconf_get_values (IBusConfigService *config,
     g_strfreev (entries);
     g_free (gdir);
 
-    return g_variant_builder_end (builder);
+    return g_variant_builder_end (&builder);
 }
 
 static gboolean
diff --git a/conf/gconf/config.c b/conf/gconf/config.c
index 5e81f7d4..73007ca7 100644
--- a/conf/gconf/config.c
+++ b/conf/gconf/config.c
@@ -304,19 +304,21 @@ ibus_config_gconf_get_values (IBusConfigService      *config,
     g_free (dir);
 
     GSList *p;
-    GVariantBuilder *builder = g_variant_builder_new (G_VARIANT_TYPE ("a{sv}"));
+    GVariantBuilder *builder;
+
+    g_variant_builder_init (&builder, G_VARIANT_TYPE ("a{sv}"));
     for (p = entries; p != NULL; p = p->next) {
         GConfEntry *entry = (GConfEntry *)p->data;
         if (entry->key != NULL && entry->value != NULL) {
             const gchar *name = entry->key + len;
             GVariant *value = _from_gconf_value (entry->value);
-            g_variant_builder_add (builder, "{sv}", name, value);
+            g_variant_builder_add (&builder, "{sv}", name, value);
         }
         gconf_entry_free (entry);
     }
     g_slist_free (entries);
 
-    return g_variant_builder_end (builder);
+    return g_variant_builder_end (&builder);
 }
 
 static gboolean
diff --git a/src/ibuscomponent.c b/src/ibuscomponent.c
index c03c9e03..2364b24a 100644
--- a/src/ibuscomponent.c
+++ b/src/ibuscomponent.c
@@ -365,6 +365,7 @@ ibus_component_serialize (IBusComponent   *component,
         g_variant_builder_add (array, "v", ibus_serializable_serialize ((IBusSerializable *)p->data));
     }
     g_variant_builder_add (builder, "av", array);
+    g_variant_builder_unref (array);
 
     /* serialize engine desc list */
     array = g_variant_builder_new (G_VARIANT_TYPE ("av"));
@@ -372,6 +373,7 @@ ibus_component_serialize (IBusComponent   *component,
         g_variant_builder_add (array, "v", ibus_serializable_serialize ((IBusSerializable *)p->data));
     }
     g_variant_builder_add (builder, "av", array);
+    g_variant_builder_unref (array);
 
     return TRUE;
 }
diff --git a/src/ibusengine.c b/src/ibusengine.c
index 7543c99c..53d57df1 100644
--- a/src/ibusengine.c
+++ b/src/ibusengine.c
@@ -1286,6 +1286,7 @@ ibus_engine_dbus_property_changed (IBusEngine  *engine,
                                             IBUS_INTERFACE_ENGINE,
                                             builder,
                                             NULL));
+    g_variant_builder_unref (builder);
 
     error = NULL;
     connection = ibus_service_get_connection ((IBusService *)engine);